1 /*
2  * Generic driver for the MPSC (UART mode) on Marvell parts (e.g., GT64240,
3  * GT64260, MV64340, MV64360, GT96100, ... ).
4  *
5  * Author: Mark A. Greer <mgreer@mvista.com>
6  *
7  * Based on an old MPSC driver that was in the linuxppc tree.  It appears to
8  * have been created by Chris Zankel (formerly of MontaVista) but there
9  * is no proper Copyright so I'm not sure.  Apparently, parts were also
10  * taken from PPCBoot (now U-Boot).  Also based on drivers/serial/8250.c
11  * by Russell King.
12  *
13  * 2004 (c) MontaVista, Software, Inc.  This file is licensed under
14  * the terms of the GNU General Public License version 2.  This program
15  * is licensed "as is" without any warranty of any kind, whether express
16  * or implied.
17  */
18 /*
19  * The MPSC interface is much like a typical network controller's interface.
20  * That is, you set up separate rings of descriptors for transmitting and
21  * receiving data.  There is also a pool of buffers with (one buffer per
22  * descriptor) that incoming data are dma'd into or outgoing data are dma'd
23  * out of.
24  *
25  * The MPSC requires two other controllers to be able to work.  The Baud Rate
26  * Generator (BRG) provides a clock at programmable frequencies which determines
27  * the baud rate.  The Serial DMA Controller (SDMA) takes incoming data from the
28  * MPSC and DMA's it into memory or DMA's outgoing data and passes it to the
29  * MPSC.  It is actually the SDMA interrupt that the driver uses to keep the
30  * transmit and receive "engines" going (i.e., indicate data has been
31  * transmitted or received).
32  *
33  * NOTES:
34  *
35  * 1) Some chips have an erratum where several regs cannot be
36  * read.  To work around that, we keep a local copy of those regs in
37  * 'mpsc_port_info'.
38  *
39  * 2) Some chips have an erratum where the ctlr will hang when the SDMA ctlr
40  * accesses system mem with coherency enabled.  For that reason, the driver
41  * assumes that coherency for that ctlr has been disabled.  This means
42  * that when in a cache coherent system, the driver has to manually manage
43  * the data cache on the areas that it touches because the dma_* macro are
44  * basically no-ops.
45  *
46  * 3) There is an erratum (on PPC) where you can't use the instruction to do
47  * a DMA_TO_DEVICE/cache clean so DMA_BIDIRECTIONAL/flushes are used in places
48  * where a DMA_TO_DEVICE/clean would have [otherwise] sufficed.
49  *
50  * 4) AFAICT, hardware flow control isn't supported by the controller --MAG.
51  */
52 
53 
54 #if defined(CONFIG_SERIAL_MPSC_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
55 #define SUPPORT_SYSRQ
56 #endif
57 
58 #include <linux/module.h>
59 #include <linux/moduleparam.h>
60 #include <linux/tty.h>
61 #include <linux/tty_flip.h>
62 #include <linux/ioport.h>
63 #include <linux/init.h>
64 #include <linux/console.h>
65 #include <linux/sysrq.h>
66 #include <linux/serial.h>
67 #include <linux/serial_core.h>
68 #include <linux/delay.h>
69 #include <linux/device.h>
70 #include <linux/dma-mapping.h>
71 #include <linux/mv643xx.h>
72 #include <linux/platform_device.h>
73 #include <linux/gfp.h>
74 
75 #include <asm/io.h>
76 #include <asm/irq.h>
77 
78 #define	MPSC_NUM_CTLRS		2
79 
80 /*
81  * Descriptors and buffers must be cache line aligned.
82  * Buffers lengths must be multiple of cache line size.
83  * Number of Tx & Rx descriptors must be powers of 2.
84  */
85 #define	MPSC_RXR_ENTRIES	32
86 #define	MPSC_RXRE_SIZE		dma_get_cache_alignment()
87 #define	MPSC_RXR_SIZE		(MPSC_RXR_ENTRIES * MPSC_RXRE_SIZE)
88 #define	MPSC_RXBE_SIZE		dma_get_cache_alignment()
89 #define	MPSC_RXB_SIZE		(MPSC_RXR_ENTRIES * MPSC_RXBE_SIZE)
90 
91 #define	MPSC_TXR_ENTRIES	32
92 #define	MPSC_TXRE_SIZE		dma_get_cache_alignment()
93 #define	MPSC_TXR_SIZE		(MPSC_TXR_ENTRIES * MPSC_TXRE_SIZE)
94 #define	MPSC_TXBE_SIZE		dma_get_cache_alignment()
95 #define	MPSC_TXB_SIZE		(MPSC_TXR_ENTRIES * MPSC_TXBE_SIZE)
96 
97 #define	MPSC_DMA_ALLOC_SIZE	(MPSC_RXR_SIZE + MPSC_RXB_SIZE + MPSC_TXR_SIZE \
98 		+ MPSC_TXB_SIZE + dma_get_cache_alignment() /* for alignment */)
99 
100 /* Rx and Tx Ring entry descriptors -- assume entry size is <= cacheline size */
101 struct mpsc_rx_desc {
102 	u16 bufsize;
103 	u16 bytecnt;
104 	u32 cmdstat;
105 	u32 link;
106 	u32 buf_ptr;
107 } __attribute((packed));
108 
109 struct mpsc_tx_desc {
110 	u16 bytecnt;
111 	u16 shadow;
112 	u32 cmdstat;
113 	u32 link;
114 	u32 buf_ptr;
115 } __attribute((packed));
116 
117 /*
118  * Some regs that have the erratum that you can't read them are are shared
119  * between the two MPSC controllers.  This struct contains those shared regs.
120  */
121 struct mpsc_shared_regs {
122 	phys_addr_t mpsc_routing_base_p;
123 	phys_addr_t sdma_intr_base_p;
124 
125 	void __iomem *mpsc_routing_base;
126 	void __iomem *sdma_intr_base;
127 
128 	u32 MPSC_MRR_m;
129 	u32 MPSC_RCRR_m;
130 	u32 MPSC_TCRR_m;
131 	u32 SDMA_INTR_CAUSE_m;
132 	u32 SDMA_INTR_MASK_m;
133 };
134 
135 /* The main driver data structure */
136 struct mpsc_port_info {
137 	struct uart_port port;	/* Overlay uart_port structure */
138 
139 	/* Internal driver state for this ctlr */
140 	u8 ready;
141 	u8 rcv_data;
142 	tcflag_t c_iflag;	/* save termios->c_iflag */
143 	tcflag_t c_cflag;	/* save termios->c_cflag */
144 
145 	/* Info passed in from platform */
146 	u8 mirror_regs;		/* Need to mirror regs? */
147 	u8 cache_mgmt;		/* Need manual cache mgmt? */
148 	u8 brg_can_tune;	/* BRG has baud tuning? */
149 	u32 brg_clk_src;
150 	u16 mpsc_max_idle;
151 	int default_baud;
152 	int default_bits;
153 	int default_parity;
154 	int default_flow;
155 
156 	/* Physical addresses of various blocks of registers (from platform) */
157 	phys_addr_t mpsc_base_p;
158 	phys_addr_t sdma_base_p;
159 	phys_addr_t brg_base_p;
160 
161 	/* Virtual addresses of various blocks of registers (from platform) */
162 	void __iomem *mpsc_base;
163 	void __iomem *sdma_base;
164 	void __iomem *brg_base;
165 
166 	/* Descriptor ring and buffer allocations */
167 	void *dma_region;
168 	dma_addr_t dma_region_p;
169 
170 	dma_addr_t rxr;		/* Rx descriptor ring */
171 	dma_addr_t rxr_p;	/* Phys addr of rxr */
172 	u8 *rxb;		/* Rx Ring I/O buf */
173 	u8 *rxb_p;		/* Phys addr of rxb */
174 	u32 rxr_posn;		/* First desc w/ Rx data */
175 
176 	dma_addr_t txr;		/* Tx descriptor ring */
177 	dma_addr_t txr_p;	/* Phys addr of txr */
178 	u8 *txb;		/* Tx Ring I/O buf */
179 	u8 *txb_p;		/* Phys addr of txb */
180 	int txr_head;		/* Where new data goes */
181 	int txr_tail;		/* Where sent data comes off */
182 	spinlock_t tx_lock;	/* transmit lock */
183 
184 	/* Mirrored values of regs we can't read (if 'mirror_regs' set) */
185 	u32 MPSC_MPCR_m;
186 	u32 MPSC_CHR_1_m;
187 	u32 MPSC_CHR_2_m;
188 	u32 MPSC_CHR_10_m;
189 	u32 BRG_BCR_m;
190 	struct mpsc_shared_regs *shared_regs;
191 };
192 
193 /* Hooks to platform-specific code */
194 int mpsc_platform_register_driver(void);
195 void mpsc_platform_unregister_driver(void);
196 
197 /* Hooks back in to mpsc common to be called by platform-specific code */
198 struct mpsc_port_info *mpsc_device_probe(int index);
199 struct mpsc_port_info *mpsc_device_remove(int index);
200 
201 /* Main MPSC Configuration Register Offsets */
202 #define	MPSC_MMCRL			0x0000
203 #define	MPSC_MMCRH			0x0004
204 #define	MPSC_MPCR			0x0008
205 #define	MPSC_CHR_1			0x000c
206 #define	MPSC_CHR_2			0x0010
207 #define	MPSC_CHR_3			0x0014
208 #define	MPSC_CHR_4			0x0018
209 #define	MPSC_CHR_5			0x001c
210 #define	MPSC_CHR_6			0x0020
211 #define	MPSC_CHR_7			0x0024
212 #define	MPSC_CHR_8			0x0028
213 #define	MPSC_CHR_9			0x002c
214 #define	MPSC_CHR_10			0x0030
215 #define	MPSC_CHR_11			0x0034
216 
217 #define	MPSC_MPCR_FRZ			(1 << 9)
218 #define	MPSC_MPCR_CL_5			0
219 #define	MPSC_MPCR_CL_6			1
220 #define	MPSC_MPCR_CL_7			2
221 #define	MPSC_MPCR_CL_8			3
222 #define	MPSC_MPCR_SBL_1			0
223 #define	MPSC_MPCR_SBL_2			1
224 
225 #define	MPSC_CHR_2_TEV			(1<<1)
226 #define	MPSC_CHR_2_TA			(1<<7)
227 #define	MPSC_CHR_2_TTCS			(1<<9)
228 #define	MPSC_CHR_2_REV			(1<<17)
229 #define	MPSC_CHR_2_RA			(1<<23)
230 #define	MPSC_CHR_2_CRD			(1<<25)
231 #define	MPSC_CHR_2_EH			(1<<31)
232 #define	MPSC_CHR_2_PAR_ODD		0
233 #define	MPSC_CHR_2_PAR_SPACE		1
234 #define	MPSC_CHR_2_PAR_EVEN		2
235 #define	MPSC_CHR_2_PAR_MARK		3
236 
237 /* MPSC Signal Routing */
238 #define	MPSC_MRR			0x0000
239 #define	MPSC_RCRR			0x0004
240 #define	MPSC_TCRR			0x0008
241 
242 /* Serial DMA Controller Interface Registers */
243 #define	SDMA_SDC			0x0000
244 #define	SDMA_SDCM			0x0008
245 #define	SDMA_RX_DESC			0x0800
246 #define	SDMA_RX_BUF_PTR			0x0808
247 #define	SDMA_SCRDP			0x0810
248 #define	SDMA_TX_DESC			0x0c00
249 #define	SDMA_SCTDP			0x0c10
250 #define	SDMA_SFTDP			0x0c14
251 
252 #define	SDMA_DESC_CMDSTAT_PE		(1<<0)
253 #define	SDMA_DESC_CMDSTAT_CDL		(1<<1)
254 #define	SDMA_DESC_CMDSTAT_FR		(1<<3)
255 #define	SDMA_DESC_CMDSTAT_OR		(1<<6)
256 #define	SDMA_DESC_CMDSTAT_BR		(1<<9)
257 #define	SDMA_DESC_CMDSTAT_MI		(1<<10)
258 #define	SDMA_DESC_CMDSTAT_A		(1<<11)
259 #define	SDMA_DESC_CMDSTAT_AM		(1<<12)
260 #define	SDMA_DESC_CMDSTAT_CT		(1<<13)
261 #define	SDMA_DESC_CMDSTAT_C		(1<<14)
262 #define	SDMA_DESC_CMDSTAT_ES		(1<<15)
263 #define	SDMA_DESC_CMDSTAT_L		(1<<16)
264 #define	SDMA_DESC_CMDSTAT_F		(1<<17)
265 #define	SDMA_DESC_CMDSTAT_P		(1<<18)
266 #define	SDMA_DESC_CMDSTAT_EI		(1<<23)
267 #define	SDMA_DESC_CMDSTAT_O		(1<<31)
268 
269 #define SDMA_DESC_DFLT			(SDMA_DESC_CMDSTAT_O \
270 		| SDMA_DESC_CMDSTAT_EI)
271 
272 #define	SDMA_SDC_RFT			(1<<0)
273 #define	SDMA_SDC_SFM			(1<<1)
274 #define	SDMA_SDC_BLMR			(1<<6)
275 #define	SDMA_SDC_BLMT			(1<<7)
276 #define	SDMA_SDC_POVR			(1<<8)
277 #define	SDMA_SDC_RIFB			(1<<9)
278 
279 #define	SDMA_SDCM_ERD			(1<<7)
280 #define	SDMA_SDCM_AR			(1<<15)
281 #define	SDMA_SDCM_STD			(1<<16)
282 #define	SDMA_SDCM_TXD			(1<<23)
283 #define	SDMA_SDCM_AT			(1<<31)
284 
285 #define	SDMA_0_CAUSE_RXBUF		(1<<0)
286 #define	SDMA_0_CAUSE_RXERR		(1<<1)
287 #define	SDMA_0_CAUSE_TXBUF		(1<<2)
288 #define	SDMA_0_CAUSE_TXEND		(1<<3)
289 #define	SDMA_1_CAUSE_RXBUF		(1<<8)
290 #define	SDMA_1_CAUSE_RXERR		(1<<9)
291 #define	SDMA_1_CAUSE_TXBUF		(1<<10)
292 #define	SDMA_1_CAUSE_TXEND		(1<<11)
293 
294 #define	SDMA_CAUSE_RX_MASK	(SDMA_0_CAUSE_RXBUF | SDMA_0_CAUSE_RXERR \
295 		| SDMA_1_CAUSE_RXBUF | SDMA_1_CAUSE_RXERR)
296 #define	SDMA_CAUSE_TX_MASK	(SDMA_0_CAUSE_TXBUF | SDMA_0_CAUSE_TXEND \
297 		| SDMA_1_CAUSE_TXBUF | SDMA_1_CAUSE_TXEND)
298 
299 /* SDMA Interrupt registers */
300 #define	SDMA_INTR_CAUSE			0x0000
301 #define	SDMA_INTR_MASK			0x0080
302 
303 /* Baud Rate Generator Interface Registers */
304 #define	BRG_BCR				0x0000
305 #define	BRG_BTR				0x0004
306 
307 /*
308  * Define how this driver is known to the outside (we've been assigned a
309  * range on the "Low-density serial ports" major).
310  */
311 #define MPSC_MAJOR			204
312 #define MPSC_MINOR_START		44
313 #define	MPSC_DRIVER_NAME		"MPSC"
314 #define	MPSC_DEV_NAME			"ttyMM"
315 #define	MPSC_VERSION			"1.00"
316 
317 static struct mpsc_port_info mpsc_ports[MPSC_NUM_CTLRS];
318 static struct mpsc_shared_regs mpsc_shared_regs;
319 static struct uart_driver mpsc_reg;
320 
321 static void mpsc_start_rx(struct mpsc_port_info *pi);
322 static void mpsc_free_ring_mem(struct mpsc_port_info *pi);
323 static void mpsc_release_port(struct uart_port *port);
324 /*
325  ******************************************************************************
326  *
327  * Baud Rate Generator Routines (BRG)
328  *
329  ******************************************************************************
330  */
mpsc_brg_init(struct mpsc_port_info * pi,u32 clk_src)331 static void mpsc_brg_init(struct mpsc_port_info *pi, u32 clk_src)
332 {
333 	u32	v;
334 
335 	v = (pi->mirror_regs) ? pi->BRG_BCR_m : readl(pi->brg_base + BRG_BCR);
336 	v = (v & ~(0xf << 18)) | ((clk_src & 0xf) << 18);
337 
338 	if (pi->brg_can_tune)
339 		v &= ~(1 << 25);
340 
341 	if (pi->mirror_regs)
342 		pi->BRG_BCR_m = v;
343 	writel(v, pi->brg_base + BRG_BCR);
344 
345 	writel(readl(pi->brg_base + BRG_BTR) & 0xffff0000,
346 		pi->brg_base + BRG_BTR);
347 }
348 
mpsc_brg_enable(struct mpsc_port_info * pi)349 static void mpsc_brg_enable(struct mpsc_port_info *pi)
350 {
351 	u32	v;
352 
353 	v = (pi->mirror_regs) ? pi->BRG_BCR_m : readl(pi->brg_base + BRG_BCR);
354 	v |= (1 << 16);
355 
356 	if (pi->mirror_regs)
357 		pi->BRG_BCR_m = v;
358 	writel(v, pi->brg_base + BRG_BCR);
359 }
360 
mpsc_brg_disable(struct mpsc_port_info * pi)361 static void mpsc_brg_disable(struct mpsc_port_info *pi)
362 {
363 	u32	v;
364 
365 	v = (pi->mirror_regs) ? pi->BRG_BCR_m : readl(pi->brg_base + BRG_BCR);
366 	v &= ~(1 << 16);
367 
368 	if (pi->mirror_regs)
369 		pi->BRG_BCR_m = v;
370 	writel(v, pi->brg_base + BRG_BCR);
371 }
372 
373 /*
374  * To set the baud, we adjust the CDV field in the BRG_BCR reg.
375  * From manual: Baud = clk / ((CDV+1)*2) ==> CDV = (clk / (baud*2)) - 1.
376  * However, the input clock is divided by 16 in the MPSC b/c of how
377  * 'MPSC_MMCRH' was set up so we have to divide the 'clk' used in our
378  * calculation by 16 to account for that.  So the real calculation
379  * that accounts for the way the mpsc is set up is:
380  * CDV = (clk / (baud*2*16)) - 1 ==> CDV = (clk / (baud << 5)) - 1.
381  */
mpsc_set_baudrate(struct mpsc_port_info * pi,u32 baud)382 static void mpsc_set_baudrate(struct mpsc_port_info *pi, u32 baud)
383 {
384 	u32	cdv = (pi->port.uartclk / (baud << 5)) - 1;
385 	u32	v;
386 
387 	mpsc_brg_disable(pi);
388 	v = (pi->mirror_regs) ? pi->BRG_BCR_m : readl(pi->brg_base + BRG_BCR);
389 	v = (v & 0xffff0000) | (cdv & 0xffff);
390 
391 	if (pi->mirror_regs)
392 		pi->BRG_BCR_m = v;
393 	writel(v, pi->brg_base + BRG_BCR);
394 	mpsc_brg_enable(pi);
395 }
396 
397 /*
398  ******************************************************************************
399  *
400  * Serial DMA Routines (SDMA)
401  *
402  ******************************************************************************
403  */
404 
mpsc_sdma_burstsize(struct mpsc_port_info * pi,u32 burst_size)405 static void mpsc_sdma_burstsize(struct mpsc_port_info *pi, u32 burst_size)
406 {
407 	u32	v;
408 
409 	pr_debug("mpsc_sdma_burstsize[%d]: burst_size: %d\n",
410 			pi->port.line, burst_size);
411 
412 	burst_size >>= 3; /* Divide by 8 b/c reg values are 8-byte chunks */
413 
414 	if (burst_size < 2)
415 		v = 0x0;	/* 1 64-bit word */
416 	else if (burst_size < 4)
417 		v = 0x1;	/* 2 64-bit words */
418 	else if (burst_size < 8)
419 		v = 0x2;	/* 4 64-bit words */
420 	else
421 		v = 0x3;	/* 8 64-bit words */
422 
423 	writel((readl(pi->sdma_base + SDMA_SDC) & (0x3 << 12)) | (v << 12),
424 		pi->sdma_base + SDMA_SDC);
425 }
426 
mpsc_sdma_init(struct mpsc_port_info * pi,u32 burst_size)427 static void mpsc_sdma_init(struct mpsc_port_info *pi, u32 burst_size)
428 {
429 	pr_debug("mpsc_sdma_init[%d]: burst_size: %d\n", pi->port.line,
430 		burst_size);
431 
432 	writel((readl(pi->sdma_base + SDMA_SDC) & 0x3ff) | 0x03f,
433 		pi->sdma_base + SDMA_SDC);
434 	mpsc_sdma_burstsize(pi, burst_size);
435 }
436 
mpsc_sdma_intr_mask(struct mpsc_port_info * pi,u32 mask)437 static u32 mpsc_sdma_intr_mask(struct mpsc_port_info *pi, u32 mask)
438 {
439 	u32	old, v;
440 
441 	pr_debug("mpsc_sdma_intr_mask[%d]: mask: 0x%x\n", pi->port.line, mask);
442 
443 	old = v = (pi->mirror_regs) ? pi->shared_regs->SDMA_INTR_MASK_m :
444 		readl(pi->shared_regs->sdma_intr_base + SDMA_INTR_MASK);
445 
446 	mask &= 0xf;
447 	if (pi->port.line)
448 		mask <<= 8;
449 	v &= ~mask;
450 
451 	if (pi->mirror_regs)
452 		pi->shared_regs->SDMA_INTR_MASK_m = v;
453 	writel(v, pi->shared_regs->sdma_intr_base + SDMA_INTR_MASK);
454 
455 	if (pi->port.line)
456 		old >>= 8;
457 	return old & 0xf;
458 }
459 
mpsc_sdma_intr_unmask(struct mpsc_port_info * pi,u32 mask)460 static void mpsc_sdma_intr_unmask(struct mpsc_port_info *pi, u32 mask)
461 {
462 	u32	v;
463 
464 	pr_debug("mpsc_sdma_intr_unmask[%d]: mask: 0x%x\n", pi->port.line,mask);
465 
466 	v = (pi->mirror_regs) ? pi->shared_regs->SDMA_INTR_MASK_m
467 		: readl(pi->shared_regs->sdma_intr_base + SDMA_INTR_MASK);
468 
469 	mask &= 0xf;
470 	if (pi->port.line)
471 		mask <<= 8;
472 	v |= mask;
473 
474 	if (pi->mirror_regs)
475 		pi->shared_regs->SDMA_INTR_MASK_m = v;
476 	writel(v, pi->shared_regs->sdma_intr_base + SDMA_INTR_MASK);
477 }
478 
mpsc_sdma_intr_ack(struct mpsc_port_info * pi)479 static void mpsc_sdma_intr_ack(struct mpsc_port_info *pi)
480 {
481 	pr_debug("mpsc_sdma_intr_ack[%d]: Acknowledging IRQ\n", pi->port.line);
482 
483 	if (pi->mirror_regs)
484 		pi->shared_regs->SDMA_INTR_CAUSE_m = 0;
485 	writeb(0x00, pi->shared_regs->sdma_intr_base + SDMA_INTR_CAUSE
486 			+ pi->port.line);
487 }
488 
mpsc_sdma_set_rx_ring(struct mpsc_port_info * pi,struct mpsc_rx_desc * rxre_p)489 static void mpsc_sdma_set_rx_ring(struct mpsc_port_info *pi,
490 		struct mpsc_rx_desc *rxre_p)
491 {
492 	pr_debug("mpsc_sdma_set_rx_ring[%d]: rxre_p: 0x%x\n",
493 		pi->port.line, (u32)rxre_p);
494 
495 	writel((u32)rxre_p, pi->sdma_base + SDMA_SCRDP);
496 }
497 
mpsc_sdma_set_tx_ring(struct mpsc_port_info * pi,struct mpsc_tx_desc * txre_p)498 static void mpsc_sdma_set_tx_ring(struct mpsc_port_info *pi,
499 		struct mpsc_tx_desc *txre_p)
500 {
501 	writel((u32)txre_p, pi->sdma_base + SDMA_SFTDP);
502 	writel((u32)txre_p, pi->sdma_base + SDMA_SCTDP);
503 }
504 
mpsc_sdma_cmd(struct mpsc_port_info * pi,u32 val)505 static void mpsc_sdma_cmd(struct mpsc_port_info *pi, u32 val)
506 {
507 	u32	v;
508 
509 	v = readl(pi->sdma_base + SDMA_SDCM);
510 	if (val)
511 		v |= val;
512 	else
513 		v = 0;
514 	wmb();
515 	writel(v, pi->sdma_base + SDMA_SDCM);
516 	wmb();
517 }
518 
mpsc_sdma_tx_active(struct mpsc_port_info * pi)519 static uint mpsc_sdma_tx_active(struct mpsc_port_info *pi)
520 {
521 	return readl(pi->sdma_base + SDMA_SDCM) & SDMA_SDCM_TXD;
522 }
523 
mpsc_sdma_start_tx(struct mpsc_port_info * pi)524 static void mpsc_sdma_start_tx(struct mpsc_port_info *pi)
525 {
526 	struct mpsc_tx_desc *txre, *txre_p;
527 
528 	/* If tx isn't running & there's a desc ready to go, start it */
529 	if (!mpsc_sdma_tx_active(pi)) {
530 		txre = (struct mpsc_tx_desc *)(pi->txr
531 				+ (pi->txr_tail * MPSC_TXRE_SIZE));
532 		dma_cache_sync(pi->port.dev, (void *)txre, MPSC_TXRE_SIZE,
533 				DMA_FROM_DEVICE);
534 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
535 		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
536 			invalidate_dcache_range((ulong)txre,
537 					(ulong)txre + MPSC_TXRE_SIZE);
538 #endif
539 
540 		if (be32_to_cpu(txre->cmdstat) & SDMA_DESC_CMDSTAT_O) {
541 			txre_p = (struct mpsc_tx_desc *)
542 				(pi->txr_p + (pi->txr_tail * MPSC_TXRE_SIZE));
543 
544 			mpsc_sdma_set_tx_ring(pi, txre_p);
545 			mpsc_sdma_cmd(pi, SDMA_SDCM_STD | SDMA_SDCM_TXD);
546 		}
547 	}
548 }
549 
mpsc_sdma_stop(struct mpsc_port_info * pi)550 static void mpsc_sdma_stop(struct mpsc_port_info *pi)
551 {
552 	pr_debug("mpsc_sdma_stop[%d]: Stopping SDMA\n", pi->port.line);
553 
554 	/* Abort any SDMA transfers */
555 	mpsc_sdma_cmd(pi, 0);
556 	mpsc_sdma_cmd(pi, SDMA_SDCM_AR | SDMA_SDCM_AT);
557 
558 	/* Clear the SDMA current and first TX and RX pointers */
559 	mpsc_sdma_set_tx_ring(pi, NULL);
560 	mpsc_sdma_set_rx_ring(pi, NULL);
561 
562 	/* Disable interrupts */
563 	mpsc_sdma_intr_mask(pi, 0xf);
564 	mpsc_sdma_intr_ack(pi);
565 }
566 
567 /*
568  ******************************************************************************
569  *
570  * Multi-Protocol Serial Controller Routines (MPSC)
571  *
572  ******************************************************************************
573  */
574 
mpsc_hw_init(struct mpsc_port_info * pi)575 static void mpsc_hw_init(struct mpsc_port_info *pi)
576 {
577 	u32	v;
578 
579 	pr_debug("mpsc_hw_init[%d]: Initializing hardware\n", pi->port.line);
580 
581 	/* Set up clock routing */
582 	if (pi->mirror_regs) {
583 		v = pi->shared_regs->MPSC_MRR_m;
584 		v &= ~0x1c7;
585 		pi->shared_regs->MPSC_MRR_m = v;
586 		writel(v, pi->shared_regs->mpsc_routing_base + MPSC_MRR);
587 
588 		v = pi->shared_regs->MPSC_RCRR_m;
589 		v = (v & ~0xf0f) | 0x100;
590 		pi->shared_regs->MPSC_RCRR_m = v;
591 		writel(v, pi->shared_regs->mpsc_routing_base + MPSC_RCRR);
592 
593 		v = pi->shared_regs->MPSC_TCRR_m;
594 		v = (v & ~0xf0f) | 0x100;
595 		pi->shared_regs->MPSC_TCRR_m = v;
596 		writel(v, pi->shared_regs->mpsc_routing_base + MPSC_TCRR);
597 	} else {
598 		v = readl(pi->shared_regs->mpsc_routing_base + MPSC_MRR);
599 		v &= ~0x1c7;
600 		writel(v, pi->shared_regs->mpsc_routing_base + MPSC_MRR);
601 
602 		v = readl(pi->shared_regs->mpsc_routing_base + MPSC_RCRR);
603 		v = (v & ~0xf0f) | 0x100;
604 		writel(v, pi->shared_regs->mpsc_routing_base + MPSC_RCRR);
605 
606 		v = readl(pi->shared_regs->mpsc_routing_base + MPSC_TCRR);
607 		v = (v & ~0xf0f) | 0x100;
608 		writel(v, pi->shared_regs->mpsc_routing_base + MPSC_TCRR);
609 	}
610 
611 	/* Put MPSC in UART mode & enabel Tx/Rx egines */
612 	writel(0x000004c4, pi->mpsc_base + MPSC_MMCRL);
613 
614 	/* No preamble, 16x divider, low-latency, */
615 	writel(0x04400400, pi->mpsc_base + MPSC_MMCRH);
616 	mpsc_set_baudrate(pi, pi->default_baud);
617 
618 	if (pi->mirror_regs) {
619 		pi->MPSC_CHR_1_m = 0;
620 		pi->MPSC_CHR_2_m = 0;
621 	}
622 	writel(0, pi->mpsc_base + MPSC_CHR_1);
623 	writel(0, pi->mpsc_base + MPSC_CHR_2);
624 	writel(pi->mpsc_max_idle, pi->mpsc_base + MPSC_CHR_3);
625 	writel(0, pi->mpsc_base + MPSC_CHR_4);
626 	writel(0, pi->mpsc_base + MPSC_CHR_5);
627 	writel(0, pi->mpsc_base + MPSC_CHR_6);
628 	writel(0, pi->mpsc_base + MPSC_CHR_7);
629 	writel(0, pi->mpsc_base + MPSC_CHR_8);
630 	writel(0, pi->mpsc_base + MPSC_CHR_9);
631 	writel(0, pi->mpsc_base + MPSC_CHR_10);
632 }
633 
mpsc_enter_hunt(struct mpsc_port_info * pi)634 static void mpsc_enter_hunt(struct mpsc_port_info *pi)
635 {
636 	pr_debug("mpsc_enter_hunt[%d]: Hunting...\n", pi->port.line);
637 
638 	if (pi->mirror_regs) {
639 		writel(pi->MPSC_CHR_2_m | MPSC_CHR_2_EH,
640 			pi->mpsc_base + MPSC_CHR_2);
641 		/* Erratum prevents reading CHR_2 so just delay for a while */
642 		udelay(100);
643 	} else {
644 		writel(readl(pi->mpsc_base + MPSC_CHR_2) | MPSC_CHR_2_EH,
645 				pi->mpsc_base + MPSC_CHR_2);
646 
647 		while (readl(pi->mpsc_base + MPSC_CHR_2) & MPSC_CHR_2_EH)
648 			udelay(10);
649 	}
650 }
651 
mpsc_freeze(struct mpsc_port_info * pi)652 static void mpsc_freeze(struct mpsc_port_info *pi)
653 {
654 	u32	v;
655 
656 	pr_debug("mpsc_freeze[%d]: Freezing\n", pi->port.line);
657 
658 	v = (pi->mirror_regs) ? pi->MPSC_MPCR_m :
659 		readl(pi->mpsc_base + MPSC_MPCR);
660 	v |= MPSC_MPCR_FRZ;
661 
662 	if (pi->mirror_regs)
663 		pi->MPSC_MPCR_m = v;
664 	writel(v, pi->mpsc_base + MPSC_MPCR);
665 }
666 
mpsc_unfreeze(struct mpsc_port_info * pi)667 static void mpsc_unfreeze(struct mpsc_port_info *pi)
668 {
669 	u32	v;
670 
671 	v = (pi->mirror_regs) ? pi->MPSC_MPCR_m :
672 		readl(pi->mpsc_base + MPSC_MPCR);
673 	v &= ~MPSC_MPCR_FRZ;
674 
675 	if (pi->mirror_regs)
676 		pi->MPSC_MPCR_m = v;
677 	writel(v, pi->mpsc_base + MPSC_MPCR);
678 
679 	pr_debug("mpsc_unfreeze[%d]: Unfrozen\n", pi->port.line);
680 }
681 
mpsc_set_char_length(struct mpsc_port_info * pi,u32 len)682 static void mpsc_set_char_length(struct mpsc_port_info *pi, u32 len)
683 {
684 	u32	v;
685 
686 	pr_debug("mpsc_set_char_length[%d]: char len: %d\n", pi->port.line,len);
687 
688 	v = (pi->mirror_regs) ? pi->MPSC_MPCR_m :
689 		readl(pi->mpsc_base + MPSC_MPCR);
690 	v = (v & ~(0x3 << 12)) | ((len & 0x3) << 12);
691 
692 	if (pi->mirror_regs)
693 		pi->MPSC_MPCR_m = v;
694 	writel(v, pi->mpsc_base + MPSC_MPCR);
695 }
696 
mpsc_set_stop_bit_length(struct mpsc_port_info * pi,u32 len)697 static void mpsc_set_stop_bit_length(struct mpsc_port_info *pi, u32 len)
698 {
699 	u32	v;
700 
701 	pr_debug("mpsc_set_stop_bit_length[%d]: stop bits: %d\n",
702 		pi->port.line, len);
703 
704 	v = (pi->mirror_regs) ? pi->MPSC_MPCR_m :
705 		readl(pi->mpsc_base + MPSC_MPCR);
706 
707 	v = (v & ~(1 << 14)) | ((len & 0x1) << 14);
708 
709 	if (pi->mirror_regs)
710 		pi->MPSC_MPCR_m = v;
711 	writel(v, pi->mpsc_base + MPSC_MPCR);
712 }
713 
mpsc_set_parity(struct mpsc_port_info * pi,u32 p)714 static void mpsc_set_parity(struct mpsc_port_info *pi, u32 p)
715 {
716 	u32	v;
717 
718 	pr_debug("mpsc_set_parity[%d]: parity bits: 0x%x\n", pi->port.line, p);
719 
720 	v = (pi->mirror_regs) ? pi->MPSC_CHR_2_m :
721 		readl(pi->mpsc_base + MPSC_CHR_2);
722 
723 	p &= 0x3;
724 	v = (v & ~0xc000c) | (p << 18) | (p << 2);
725 
726 	if (pi->mirror_regs)
727 		pi->MPSC_CHR_2_m = v;
728 	writel(v, pi->mpsc_base + MPSC_CHR_2);
729 }
730 
731 /*
732  ******************************************************************************
733  *
734  * Driver Init Routines
735  *
736  ******************************************************************************
737  */
738 
mpsc_init_hw(struct mpsc_port_info * pi)739 static void mpsc_init_hw(struct mpsc_port_info *pi)
740 {
741 	pr_debug("mpsc_init_hw[%d]: Initializing\n", pi->port.line);
742 
743 	mpsc_brg_init(pi, pi->brg_clk_src);
744 	mpsc_brg_enable(pi);
745 	mpsc_sdma_init(pi, dma_get_cache_alignment());	/* burst a cacheline */
746 	mpsc_sdma_stop(pi);
747 	mpsc_hw_init(pi);
748 }
749 
mpsc_alloc_ring_mem(struct mpsc_port_info * pi)750 static int mpsc_alloc_ring_mem(struct mpsc_port_info *pi)
751 {
752 	int rc = 0;
753 
754 	pr_debug("mpsc_alloc_ring_mem[%d]: Allocating ring mem\n",
755 		pi->port.line);
756 
757 	if (!pi->dma_region) {
758 		if (!dma_supported(pi->port.dev, 0xffffffff)) {
759 			printk(KERN_ERR "MPSC: Inadequate DMA support\n");
760 			rc = -ENXIO;
761 		} else if ((pi->dma_region = dma_alloc_noncoherent(pi->port.dev,
762 						MPSC_DMA_ALLOC_SIZE,
763 						&pi->dma_region_p, GFP_KERNEL))
764 				== NULL) {
765 			printk(KERN_ERR "MPSC: Can't alloc Desc region\n");
766 			rc = -ENOMEM;
767 		}
768 	}
769 
770 	return rc;
771 }
772 
mpsc_free_ring_mem(struct mpsc_port_info * pi)773 static void mpsc_free_ring_mem(struct mpsc_port_info *pi)
774 {
775 	pr_debug("mpsc_free_ring_mem[%d]: Freeing ring mem\n", pi->port.line);
776 
777 	if (pi->dma_region) {
778 		dma_free_noncoherent(pi->port.dev, MPSC_DMA_ALLOC_SIZE,
779 				pi->dma_region, pi->dma_region_p);
780 		pi->dma_region = NULL;
781 		pi->dma_region_p = (dma_addr_t)NULL;
782 	}
783 }
784 
mpsc_init_rings(struct mpsc_port_info * pi)785 static void mpsc_init_rings(struct mpsc_port_info *pi)
786 {
787 	struct mpsc_rx_desc *rxre;
788 	struct mpsc_tx_desc *txre;
789 	dma_addr_t dp, dp_p;
790 	u8 *bp, *bp_p;
791 	int i;
792 
793 	pr_debug("mpsc_init_rings[%d]: Initializing rings\n", pi->port.line);
794 
795 	BUG_ON(pi->dma_region == NULL);
796 
797 	memset(pi->dma_region, 0, MPSC_DMA_ALLOC_SIZE);
798 
799 	/*
800 	 * Descriptors & buffers are multiples of cacheline size and must be
801 	 * cacheline aligned.
802 	 */
803 	dp = ALIGN((u32)pi->dma_region, dma_get_cache_alignment());
804 	dp_p = ALIGN((u32)pi->dma_region_p, dma_get_cache_alignment());
805 
806 	/*
807 	 * Partition dma region into rx ring descriptor, rx buffers,
808 	 * tx ring descriptors, and tx buffers.
809 	 */
810 	pi->rxr = dp;
811 	pi->rxr_p = dp_p;
812 	dp += MPSC_RXR_SIZE;
813 	dp_p += MPSC_RXR_SIZE;
814 
815 	pi->rxb = (u8 *)dp;
816 	pi->rxb_p = (u8 *)dp_p;
817 	dp += MPSC_RXB_SIZE;
818 	dp_p += MPSC_RXB_SIZE;
819 
820 	pi->rxr_posn = 0;
821 
822 	pi->txr = dp;
823 	pi->txr_p = dp_p;
824 	dp += MPSC_TXR_SIZE;
825 	dp_p += MPSC_TXR_SIZE;
826 
827 	pi->txb = (u8 *)dp;
828 	pi->txb_p = (u8 *)dp_p;
829 
830 	pi->txr_head = 0;
831 	pi->txr_tail = 0;
832 
833 	/* Init rx ring descriptors */
834 	dp = pi->rxr;
835 	dp_p = pi->rxr_p;
836 	bp = pi->rxb;
837 	bp_p = pi->rxb_p;
838 
839 	for (i = 0; i < MPSC_RXR_ENTRIES; i++) {
840 		rxre = (struct mpsc_rx_desc *)dp;
841 
842 		rxre->bufsize = cpu_to_be16(MPSC_RXBE_SIZE);
843 		rxre->bytecnt = cpu_to_be16(0);
844 		rxre->cmdstat = cpu_to_be32(SDMA_DESC_CMDSTAT_O
845 				| SDMA_DESC_CMDSTAT_EI | SDMA_DESC_CMDSTAT_F
846 				| SDMA_DESC_CMDSTAT_L);
847 		rxre->link = cpu_to_be32(dp_p + MPSC_RXRE_SIZE);
848 		rxre->buf_ptr = cpu_to_be32(bp_p);
849 
850 		dp += MPSC_RXRE_SIZE;
851 		dp_p += MPSC_RXRE_SIZE;
852 		bp += MPSC_RXBE_SIZE;
853 		bp_p += MPSC_RXBE_SIZE;
854 	}
855 	rxre->link = cpu_to_be32(pi->rxr_p);	/* Wrap last back to first */
856 
857 	/* Init tx ring descriptors */
858 	dp = pi->txr;
859 	dp_p = pi->txr_p;
860 	bp = pi->txb;
861 	bp_p = pi->txb_p;
862 
863 	for (i = 0; i < MPSC_TXR_ENTRIES; i++) {
864 		txre = (struct mpsc_tx_desc *)dp;
865 
866 		txre->link = cpu_to_be32(dp_p + MPSC_TXRE_SIZE);
867 		txre->buf_ptr = cpu_to_be32(bp_p);
868 
869 		dp += MPSC_TXRE_SIZE;
870 		dp_p += MPSC_TXRE_SIZE;
871 		bp += MPSC_TXBE_SIZE;
872 		bp_p += MPSC_TXBE_SIZE;
873 	}
874 	txre->link = cpu_to_be32(pi->txr_p);	/* Wrap last back to first */
875 
876 	dma_cache_sync(pi->port.dev, (void *)pi->dma_region,
877 			MPSC_DMA_ALLOC_SIZE, DMA_BIDIRECTIONAL);
878 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
879 		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
880 			flush_dcache_range((ulong)pi->dma_region,
881 					(ulong)pi->dma_region
882 					+ MPSC_DMA_ALLOC_SIZE);
883 #endif
884 
885 	return;
886 }
887 
mpsc_uninit_rings(struct mpsc_port_info * pi)888 static void mpsc_uninit_rings(struct mpsc_port_info *pi)
889 {
890 	pr_debug("mpsc_uninit_rings[%d]: Uninitializing rings\n",pi->port.line);
891 
892 	BUG_ON(pi->dma_region == NULL);
893 
894 	pi->rxr = 0;
895 	pi->rxr_p = 0;
896 	pi->rxb = NULL;
897 	pi->rxb_p = NULL;
898 	pi->rxr_posn = 0;
899 
900 	pi->txr = 0;
901 	pi->txr_p = 0;
902 	pi->txb = NULL;
903 	pi->txb_p = NULL;
904 	pi->txr_head = 0;
905 	pi->txr_tail = 0;
906 }
907 
mpsc_make_ready(struct mpsc_port_info * pi)908 static int mpsc_make_ready(struct mpsc_port_info *pi)
909 {
910 	int rc;
911 
912 	pr_debug("mpsc_make_ready[%d]: Making cltr ready\n", pi->port.line);
913 
914 	if (!pi->ready) {
915 		mpsc_init_hw(pi);
916 		if ((rc = mpsc_alloc_ring_mem(pi)))
917 			return rc;
918 		mpsc_init_rings(pi);
919 		pi->ready = 1;
920 	}
921 
922 	return 0;
923 }
924 
925 #ifdef CONFIG_CONSOLE_POLL
926 static int serial_polled;
927 #endif
928 
929 /*
930  ******************************************************************************
931  *
932  * Interrupt Handling Routines
933  *
934  ******************************************************************************
935  */
936 
mpsc_rx_intr(struct mpsc_port_info * pi,unsigned long * flags)937 static int mpsc_rx_intr(struct mpsc_port_info *pi, unsigned long *flags)
938 {
939 	struct mpsc_rx_desc *rxre;
940 	struct tty_port *port = &pi->port.state->port;
941 	u32	cmdstat, bytes_in, i;
942 	int	rc = 0;
943 	u8	*bp;
944 	char	flag = TTY_NORMAL;
945 
946 	pr_debug("mpsc_rx_intr[%d]: Handling Rx intr\n", pi->port.line);
947 
948 	rxre = (struct mpsc_rx_desc *)(pi->rxr + (pi->rxr_posn*MPSC_RXRE_SIZE));
949 
950 	dma_cache_sync(pi->port.dev, (void *)rxre, MPSC_RXRE_SIZE,
951 			DMA_FROM_DEVICE);
952 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
953 	if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
954 		invalidate_dcache_range((ulong)rxre,
955 				(ulong)rxre + MPSC_RXRE_SIZE);
956 #endif
957 
958 	/*
959 	 * Loop through Rx descriptors handling ones that have been completed.
960 	 */
961 	while (!((cmdstat = be32_to_cpu(rxre->cmdstat))
962 				& SDMA_DESC_CMDSTAT_O)) {
963 		bytes_in = be16_to_cpu(rxre->bytecnt);
964 #ifdef CONFIG_CONSOLE_POLL
965 		if (unlikely(serial_polled)) {
966 			serial_polled = 0;
967 			return 0;
968 		}
969 #endif
970 		/* Following use of tty struct directly is deprecated */
971 		if (tty_buffer_request_room(port, bytes_in) < bytes_in) {
972 			if (port->low_latency) {
973 				spin_unlock_irqrestore(&pi->port.lock, *flags);
974 				tty_flip_buffer_push(port);
975 				spin_lock_irqsave(&pi->port.lock, *flags);
976 			}
977 			/*
978 			 * If this failed then we will throw away the bytes
979 			 * but must do so to clear interrupts.
980 			 */
981 		}
982 
983 		bp = pi->rxb + (pi->rxr_posn * MPSC_RXBE_SIZE);
984 		dma_cache_sync(pi->port.dev, (void *)bp, MPSC_RXBE_SIZE,
985 				DMA_FROM_DEVICE);
986 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
987 		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
988 			invalidate_dcache_range((ulong)bp,
989 					(ulong)bp + MPSC_RXBE_SIZE);
990 #endif
991 
992 		/*
993 		 * Other than for parity error, the manual provides little
994 		 * info on what data will be in a frame flagged by any of
995 		 * these errors.  For parity error, it is the last byte in
996 		 * the buffer that had the error.  As for the rest, I guess
997 		 * we'll assume there is no data in the buffer.
998 		 * If there is...it gets lost.
999 		 */
1000 		if (unlikely(cmdstat & (SDMA_DESC_CMDSTAT_BR
1001 						| SDMA_DESC_CMDSTAT_FR
1002 						| SDMA_DESC_CMDSTAT_OR))) {
1003 
1004 			pi->port.icount.rx++;
1005 
1006 			if (cmdstat & SDMA_DESC_CMDSTAT_BR) {	/* Break */
1007 				pi->port.icount.brk++;
1008 
1009 				if (uart_handle_break(&pi->port))
1010 					goto next_frame;
1011 			} else if (cmdstat & SDMA_DESC_CMDSTAT_FR) {
1012 				pi->port.icount.frame++;
1013 			} else if (cmdstat & SDMA_DESC_CMDSTAT_OR) {
1014 				pi->port.icount.overrun++;
1015 			}
1016 
1017 			cmdstat &= pi->port.read_status_mask;
1018 
1019 			if (cmdstat & SDMA_DESC_CMDSTAT_BR)
1020 				flag = TTY_BREAK;
1021 			else if (cmdstat & SDMA_DESC_CMDSTAT_FR)
1022 				flag = TTY_FRAME;
1023 			else if (cmdstat & SDMA_DESC_CMDSTAT_OR)
1024 				flag = TTY_OVERRUN;
1025 			else if (cmdstat & SDMA_DESC_CMDSTAT_PE)
1026 				flag = TTY_PARITY;
1027 		}
1028 
1029 		if (uart_handle_sysrq_char(&pi->port, *bp)) {
1030 			bp++;
1031 			bytes_in--;
1032 #ifdef CONFIG_CONSOLE_POLL
1033 			if (unlikely(serial_polled)) {
1034 				serial_polled = 0;
1035 				return 0;
1036 			}
1037 #endif
1038 			goto next_frame;
1039 		}
1040 
1041 		if ((unlikely(cmdstat & (SDMA_DESC_CMDSTAT_BR
1042 						| SDMA_DESC_CMDSTAT_FR
1043 						| SDMA_DESC_CMDSTAT_OR)))
1044 				&& !(cmdstat & pi->port.ignore_status_mask)) {
1045 			tty_insert_flip_char(port, *bp, flag);
1046 		} else {
1047 			for (i=0; i<bytes_in; i++)
1048 				tty_insert_flip_char(port, *bp++, TTY_NORMAL);
1049 
1050 			pi->port.icount.rx += bytes_in;
1051 		}
1052 
1053 next_frame:
1054 		rxre->bytecnt = cpu_to_be16(0);
1055 		wmb();
1056 		rxre->cmdstat = cpu_to_be32(SDMA_DESC_CMDSTAT_O
1057 				| SDMA_DESC_CMDSTAT_EI | SDMA_DESC_CMDSTAT_F
1058 				| SDMA_DESC_CMDSTAT_L);
1059 		wmb();
1060 		dma_cache_sync(pi->port.dev, (void *)rxre, MPSC_RXRE_SIZE,
1061 				DMA_BIDIRECTIONAL);
1062 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1063 		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1064 			flush_dcache_range((ulong)rxre,
1065 					(ulong)rxre + MPSC_RXRE_SIZE);
1066 #endif
1067 
1068 		/* Advance to next descriptor */
1069 		pi->rxr_posn = (pi->rxr_posn + 1) & (MPSC_RXR_ENTRIES - 1);
1070 		rxre = (struct mpsc_rx_desc *)
1071 			(pi->rxr + (pi->rxr_posn * MPSC_RXRE_SIZE));
1072 		dma_cache_sync(pi->port.dev, (void *)rxre, MPSC_RXRE_SIZE,
1073 				DMA_FROM_DEVICE);
1074 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1075 		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1076 			invalidate_dcache_range((ulong)rxre,
1077 					(ulong)rxre + MPSC_RXRE_SIZE);
1078 #endif
1079 		rc = 1;
1080 	}
1081 
1082 	/* Restart rx engine, if its stopped */
1083 	if ((readl(pi->sdma_base + SDMA_SDCM) & SDMA_SDCM_ERD) == 0)
1084 		mpsc_start_rx(pi);
1085 
1086 	spin_unlock_irqrestore(&pi->port.lock, *flags);
1087 	tty_flip_buffer_push(port);
1088 	spin_lock_irqsave(&pi->port.lock, *flags);
1089 	return rc;
1090 }
1091 
mpsc_setup_tx_desc(struct mpsc_port_info * pi,u32 count,u32 intr)1092 static void mpsc_setup_tx_desc(struct mpsc_port_info *pi, u32 count, u32 intr)
1093 {
1094 	struct mpsc_tx_desc *txre;
1095 
1096 	txre = (struct mpsc_tx_desc *)(pi->txr
1097 			+ (pi->txr_head * MPSC_TXRE_SIZE));
1098 
1099 	txre->bytecnt = cpu_to_be16(count);
1100 	txre->shadow = txre->bytecnt;
1101 	wmb();			/* ensure cmdstat is last field updated */
1102 	txre->cmdstat = cpu_to_be32(SDMA_DESC_CMDSTAT_O | SDMA_DESC_CMDSTAT_F
1103 			| SDMA_DESC_CMDSTAT_L
1104 			| ((intr) ? SDMA_DESC_CMDSTAT_EI : 0));
1105 	wmb();
1106 	dma_cache_sync(pi->port.dev, (void *)txre, MPSC_TXRE_SIZE,
1107 			DMA_BIDIRECTIONAL);
1108 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1109 	if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1110 		flush_dcache_range((ulong)txre,
1111 				(ulong)txre + MPSC_TXRE_SIZE);
1112 #endif
1113 }
1114 
mpsc_copy_tx_data(struct mpsc_port_info * pi)1115 static void mpsc_copy_tx_data(struct mpsc_port_info *pi)
1116 {
1117 	struct circ_buf *xmit = &pi->port.state->xmit;
1118 	u8 *bp;
1119 	u32 i;
1120 
1121 	/* Make sure the desc ring isn't full */
1122 	while (CIRC_CNT(pi->txr_head, pi->txr_tail, MPSC_TXR_ENTRIES)
1123 			< (MPSC_TXR_ENTRIES - 1)) {
1124 		if (pi->port.x_char) {
1125 			/*
1126 			 * Ideally, we should use the TCS field in
1127 			 * CHR_1 to put the x_char out immediately but
1128 			 * errata prevents us from being able to read
1129 			 * CHR_2 to know that its safe to write to
1130 			 * CHR_1.  Instead, just put it in-band with
1131 			 * all the other Tx data.
1132 			 */
1133 			bp = pi->txb + (pi->txr_head * MPSC_TXBE_SIZE);
1134 			*bp = pi->port.x_char;
1135 			pi->port.x_char = 0;
1136 			i = 1;
1137 		} else if (!uart_circ_empty(xmit)
1138 				&& !uart_tx_stopped(&pi->port)) {
1139 			i = min((u32)MPSC_TXBE_SIZE,
1140 				(u32)uart_circ_chars_pending(xmit));
1141 			i = min(i, (u32)CIRC_CNT_TO_END(xmit->head, xmit->tail,
1142 				UART_XMIT_SIZE));
1143 			bp = pi->txb + (pi->txr_head * MPSC_TXBE_SIZE);
1144 			memcpy(bp, &xmit->buf[xmit->tail], i);
1145 			xmit->tail = (xmit->tail + i) & (UART_XMIT_SIZE - 1);
1146 
1147 			if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1148 				uart_write_wakeup(&pi->port);
1149 		} else { /* All tx data copied into ring bufs */
1150 			return;
1151 		}
1152 
1153 		dma_cache_sync(pi->port.dev, (void *)bp, MPSC_TXBE_SIZE,
1154 				DMA_BIDIRECTIONAL);
1155 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1156 		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1157 			flush_dcache_range((ulong)bp,
1158 					(ulong)bp + MPSC_TXBE_SIZE);
1159 #endif
1160 		mpsc_setup_tx_desc(pi, i, 1);
1161 
1162 		/* Advance to next descriptor */
1163 		pi->txr_head = (pi->txr_head + 1) & (MPSC_TXR_ENTRIES - 1);
1164 	}
1165 }
1166 
mpsc_tx_intr(struct mpsc_port_info * pi)1167 static int mpsc_tx_intr(struct mpsc_port_info *pi)
1168 {
1169 	struct mpsc_tx_desc *txre;
1170 	int rc = 0;
1171 	unsigned long iflags;
1172 
1173 	spin_lock_irqsave(&pi->tx_lock, iflags);
1174 
1175 	if (!mpsc_sdma_tx_active(pi)) {
1176 		txre = (struct mpsc_tx_desc *)(pi->txr
1177 				+ (pi->txr_tail * MPSC_TXRE_SIZE));
1178 
1179 		dma_cache_sync(pi->port.dev, (void *)txre, MPSC_TXRE_SIZE,
1180 				DMA_FROM_DEVICE);
1181 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1182 		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1183 			invalidate_dcache_range((ulong)txre,
1184 					(ulong)txre + MPSC_TXRE_SIZE);
1185 #endif
1186 
1187 		while (!(be32_to_cpu(txre->cmdstat) & SDMA_DESC_CMDSTAT_O)) {
1188 			rc = 1;
1189 			pi->port.icount.tx += be16_to_cpu(txre->bytecnt);
1190 			pi->txr_tail = (pi->txr_tail+1) & (MPSC_TXR_ENTRIES-1);
1191 
1192 			/* If no more data to tx, fall out of loop */
1193 			if (pi->txr_head == pi->txr_tail)
1194 				break;
1195 
1196 			txre = (struct mpsc_tx_desc *)(pi->txr
1197 					+ (pi->txr_tail * MPSC_TXRE_SIZE));
1198 			dma_cache_sync(pi->port.dev, (void *)txre,
1199 					MPSC_TXRE_SIZE, DMA_FROM_DEVICE);
1200 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1201 			if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1202 				invalidate_dcache_range((ulong)txre,
1203 						(ulong)txre + MPSC_TXRE_SIZE);
1204 #endif
1205 		}
1206 
1207 		mpsc_copy_tx_data(pi);
1208 		mpsc_sdma_start_tx(pi);	/* start next desc if ready */
1209 	}
1210 
1211 	spin_unlock_irqrestore(&pi->tx_lock, iflags);
1212 	return rc;
1213 }
1214 
1215 /*
1216  * This is the driver's interrupt handler.  To avoid a race, we first clear
1217  * the interrupt, then handle any completed Rx/Tx descriptors.  When done
1218  * handling those descriptors, we restart the Rx/Tx engines if they're stopped.
1219  */
mpsc_sdma_intr(int irq,void * dev_id)1220 static irqreturn_t mpsc_sdma_intr(int irq, void *dev_id)
1221 {
1222 	struct mpsc_port_info *pi = dev_id;
1223 	ulong iflags;
1224 	int rc = IRQ_NONE;
1225 
1226 	pr_debug("mpsc_sdma_intr[%d]: SDMA Interrupt Received\n",pi->port.line);
1227 
1228 	spin_lock_irqsave(&pi->port.lock, iflags);
1229 	mpsc_sdma_intr_ack(pi);
1230 	if (mpsc_rx_intr(pi, &iflags))
1231 		rc = IRQ_HANDLED;
1232 	if (mpsc_tx_intr(pi))
1233 		rc = IRQ_HANDLED;
1234 	spin_unlock_irqrestore(&pi->port.lock, iflags);
1235 
1236 	pr_debug("mpsc_sdma_intr[%d]: SDMA Interrupt Handled\n", pi->port.line);
1237 	return rc;
1238 }
1239 
1240 /*
1241  ******************************************************************************
1242  *
1243  * serial_core.c Interface routines
1244  *
1245  ******************************************************************************
1246  */
mpsc_tx_empty(struct uart_port * port)1247 static uint mpsc_tx_empty(struct uart_port *port)
1248 {
1249 	struct mpsc_port_info *pi =
1250 		container_of(port, struct mpsc_port_info, port);
1251 	ulong iflags;
1252 	uint rc;
1253 
1254 	spin_lock_irqsave(&pi->port.lock, iflags);
1255 	rc = mpsc_sdma_tx_active(pi) ? 0 : TIOCSER_TEMT;
1256 	spin_unlock_irqrestore(&pi->port.lock, iflags);
1257 
1258 	return rc;
1259 }
1260 
mpsc_set_mctrl(struct uart_port * port,uint mctrl)1261 static void mpsc_set_mctrl(struct uart_port *port, uint mctrl)
1262 {
1263 	/* Have no way to set modem control lines AFAICT */
1264 }
1265 
mpsc_get_mctrl(struct uart_port * port)1266 static uint mpsc_get_mctrl(struct uart_port *port)
1267 {
1268 	struct mpsc_port_info *pi =
1269 		container_of(port, struct mpsc_port_info, port);
1270 	u32 mflags, status;
1271 
1272 	status = (pi->mirror_regs) ? pi->MPSC_CHR_10_m
1273 		: readl(pi->mpsc_base + MPSC_CHR_10);
1274 
1275 	mflags = 0;
1276 	if (status & 0x1)
1277 		mflags |= TIOCM_CTS;
1278 	if (status & 0x2)
1279 		mflags |= TIOCM_CAR;
1280 
1281 	return mflags | TIOCM_DSR;	/* No way to tell if DSR asserted */
1282 }
1283 
mpsc_stop_tx(struct uart_port * port)1284 static void mpsc_stop_tx(struct uart_port *port)
1285 {
1286 	struct mpsc_port_info *pi =
1287 		container_of(port, struct mpsc_port_info, port);
1288 
1289 	pr_debug("mpsc_stop_tx[%d]\n", port->line);
1290 
1291 	mpsc_freeze(pi);
1292 }
1293 
mpsc_start_tx(struct uart_port * port)1294 static void mpsc_start_tx(struct uart_port *port)
1295 {
1296 	struct mpsc_port_info *pi =
1297 		container_of(port, struct mpsc_port_info, port);
1298 	unsigned long iflags;
1299 
1300 	spin_lock_irqsave(&pi->tx_lock, iflags);
1301 
1302 	mpsc_unfreeze(pi);
1303 	mpsc_copy_tx_data(pi);
1304 	mpsc_sdma_start_tx(pi);
1305 
1306 	spin_unlock_irqrestore(&pi->tx_lock, iflags);
1307 
1308 	pr_debug("mpsc_start_tx[%d]\n", port->line);
1309 }
1310 
mpsc_start_rx(struct mpsc_port_info * pi)1311 static void mpsc_start_rx(struct mpsc_port_info *pi)
1312 {
1313 	pr_debug("mpsc_start_rx[%d]: Starting...\n", pi->port.line);
1314 
1315 	if (pi->rcv_data) {
1316 		mpsc_enter_hunt(pi);
1317 		mpsc_sdma_cmd(pi, SDMA_SDCM_ERD);
1318 	}
1319 }
1320 
mpsc_stop_rx(struct uart_port * port)1321 static void mpsc_stop_rx(struct uart_port *port)
1322 {
1323 	struct mpsc_port_info *pi =
1324 		container_of(port, struct mpsc_port_info, port);
1325 
1326 	pr_debug("mpsc_stop_rx[%d]: Stopping...\n", port->line);
1327 
1328 	if (pi->mirror_regs) {
1329 		writel(pi->MPSC_CHR_2_m | MPSC_CHR_2_RA,
1330 				pi->mpsc_base + MPSC_CHR_2);
1331 		/* Erratum prevents reading CHR_2 so just delay for a while */
1332 		udelay(100);
1333 	} else {
1334 		writel(readl(pi->mpsc_base + MPSC_CHR_2) | MPSC_CHR_2_RA,
1335 				pi->mpsc_base + MPSC_CHR_2);
1336 
1337 		while (readl(pi->mpsc_base + MPSC_CHR_2) & MPSC_CHR_2_RA)
1338 			udelay(10);
1339 	}
1340 
1341 	mpsc_sdma_cmd(pi, SDMA_SDCM_AR);
1342 }
1343 
mpsc_break_ctl(struct uart_port * port,int ctl)1344 static void mpsc_break_ctl(struct uart_port *port, int ctl)
1345 {
1346 	struct mpsc_port_info *pi =
1347 		container_of(port, struct mpsc_port_info, port);
1348 	ulong	flags;
1349 	u32	v;
1350 
1351 	v = ctl ? 0x00ff0000 : 0;
1352 
1353 	spin_lock_irqsave(&pi->port.lock, flags);
1354 	if (pi->mirror_regs)
1355 		pi->MPSC_CHR_1_m = v;
1356 	writel(v, pi->mpsc_base + MPSC_CHR_1);
1357 	spin_unlock_irqrestore(&pi->port.lock, flags);
1358 }
1359 
mpsc_startup(struct uart_port * port)1360 static int mpsc_startup(struct uart_port *port)
1361 {
1362 	struct mpsc_port_info *pi =
1363 		container_of(port, struct mpsc_port_info, port);
1364 	u32 flag = 0;
1365 	int rc;
1366 
1367 	pr_debug("mpsc_startup[%d]: Starting up MPSC, irq: %d\n",
1368 		port->line, pi->port.irq);
1369 
1370 	if ((rc = mpsc_make_ready(pi)) == 0) {
1371 		/* Setup IRQ handler */
1372 		mpsc_sdma_intr_ack(pi);
1373 
1374 		/* If irq's are shared, need to set flag */
1375 		if (mpsc_ports[0].port.irq == mpsc_ports[1].port.irq)
1376 			flag = IRQF_SHARED;
1377 
1378 		if (request_irq(pi->port.irq, mpsc_sdma_intr, flag,
1379 					"mpsc-sdma", pi))
1380 			printk(KERN_ERR "MPSC: Can't get SDMA IRQ %d\n",
1381 					pi->port.irq);
1382 
1383 		mpsc_sdma_intr_unmask(pi, 0xf);
1384 		mpsc_sdma_set_rx_ring(pi, (struct mpsc_rx_desc *)(pi->rxr_p
1385 					+ (pi->rxr_posn * MPSC_RXRE_SIZE)));
1386 	}
1387 
1388 	return rc;
1389 }
1390 
mpsc_shutdown(struct uart_port * port)1391 static void mpsc_shutdown(struct uart_port *port)
1392 {
1393 	struct mpsc_port_info *pi =
1394 		container_of(port, struct mpsc_port_info, port);
1395 
1396 	pr_debug("mpsc_shutdown[%d]: Shutting down MPSC\n", port->line);
1397 
1398 	mpsc_sdma_stop(pi);
1399 	free_irq(pi->port.irq, pi);
1400 }
1401 
mpsc_set_termios(struct uart_port * port,struct ktermios * termios,struct ktermios * old)1402 static void mpsc_set_termios(struct uart_port *port, struct ktermios *termios,
1403 		 struct ktermios *old)
1404 {
1405 	struct mpsc_port_info *pi =
1406 		container_of(port, struct mpsc_port_info, port);
1407 	u32 baud;
1408 	ulong flags;
1409 	u32 chr_bits, stop_bits, par;
1410 
1411 	pi->c_iflag = termios->c_iflag;
1412 	pi->c_cflag = termios->c_cflag;
1413 
1414 	switch (termios->c_cflag & CSIZE) {
1415 	case CS5:
1416 		chr_bits = MPSC_MPCR_CL_5;
1417 		break;
1418 	case CS6:
1419 		chr_bits = MPSC_MPCR_CL_6;
1420 		break;
1421 	case CS7:
1422 		chr_bits = MPSC_MPCR_CL_7;
1423 		break;
1424 	case CS8:
1425 	default:
1426 		chr_bits = MPSC_MPCR_CL_8;
1427 		break;
1428 	}
1429 
1430 	if (termios->c_cflag & CSTOPB)
1431 		stop_bits = MPSC_MPCR_SBL_2;
1432 	else
1433 		stop_bits = MPSC_MPCR_SBL_1;
1434 
1435 	par = MPSC_CHR_2_PAR_EVEN;
1436 	if (termios->c_cflag & PARENB)
1437 		if (termios->c_cflag & PARODD)
1438 			par = MPSC_CHR_2_PAR_ODD;
1439 #ifdef	CMSPAR
1440 		if (termios->c_cflag & CMSPAR) {
1441 			if (termios->c_cflag & PARODD)
1442 				par = MPSC_CHR_2_PAR_MARK;
1443 			else
1444 				par = MPSC_CHR_2_PAR_SPACE;
1445 		}
1446 #endif
1447 
1448 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk);
1449 
1450 	spin_lock_irqsave(&pi->port.lock, flags);
1451 
1452 	uart_update_timeout(port, termios->c_cflag, baud);
1453 
1454 	mpsc_set_char_length(pi, chr_bits);
1455 	mpsc_set_stop_bit_length(pi, stop_bits);
1456 	mpsc_set_parity(pi, par);
1457 	mpsc_set_baudrate(pi, baud);
1458 
1459 	/* Characters/events to read */
1460 	pi->port.read_status_mask = SDMA_DESC_CMDSTAT_OR;
1461 
1462 	if (termios->c_iflag & INPCK)
1463 		pi->port.read_status_mask |= SDMA_DESC_CMDSTAT_PE
1464 			| SDMA_DESC_CMDSTAT_FR;
1465 
1466 	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
1467 		pi->port.read_status_mask |= SDMA_DESC_CMDSTAT_BR;
1468 
1469 	/* Characters/events to ignore */
1470 	pi->port.ignore_status_mask = 0;
1471 
1472 	if (termios->c_iflag & IGNPAR)
1473 		pi->port.ignore_status_mask |= SDMA_DESC_CMDSTAT_PE
1474 			| SDMA_DESC_CMDSTAT_FR;
1475 
1476 	if (termios->c_iflag & IGNBRK) {
1477 		pi->port.ignore_status_mask |= SDMA_DESC_CMDSTAT_BR;
1478 
1479 		if (termios->c_iflag & IGNPAR)
1480 			pi->port.ignore_status_mask |= SDMA_DESC_CMDSTAT_OR;
1481 	}
1482 
1483 	if ((termios->c_cflag & CREAD)) {
1484 		if (!pi->rcv_data) {
1485 			pi->rcv_data = 1;
1486 			mpsc_start_rx(pi);
1487 		}
1488 	} else if (pi->rcv_data) {
1489 		mpsc_stop_rx(port);
1490 		pi->rcv_data = 0;
1491 	}
1492 
1493 	spin_unlock_irqrestore(&pi->port.lock, flags);
1494 }
1495 
mpsc_type(struct uart_port * port)1496 static const char *mpsc_type(struct uart_port *port)
1497 {
1498 	pr_debug("mpsc_type[%d]: port type: %s\n", port->line,MPSC_DRIVER_NAME);
1499 	return MPSC_DRIVER_NAME;
1500 }
1501 
mpsc_request_port(struct uart_port * port)1502 static int mpsc_request_port(struct uart_port *port)
1503 {
1504 	/* Should make chip/platform specific call */
1505 	return 0;
1506 }
1507 
mpsc_release_port(struct uart_port * port)1508 static void mpsc_release_port(struct uart_port *port)
1509 {
1510 	struct mpsc_port_info *pi =
1511 		container_of(port, struct mpsc_port_info, port);
1512 
1513 	if (pi->ready) {
1514 		mpsc_uninit_rings(pi);
1515 		mpsc_free_ring_mem(pi);
1516 		pi->ready = 0;
1517 	}
1518 }
1519 
mpsc_config_port(struct uart_port * port,int flags)1520 static void mpsc_config_port(struct uart_port *port, int flags)
1521 {
1522 }
1523 
mpsc_verify_port(struct uart_port * port,struct serial_struct * ser)1524 static int mpsc_verify_port(struct uart_port *port, struct serial_struct *ser)
1525 {
1526 	struct mpsc_port_info *pi =
1527 		container_of(port, struct mpsc_port_info, port);
1528 	int rc = 0;
1529 
1530 	pr_debug("mpsc_verify_port[%d]: Verifying port data\n", pi->port.line);
1531 
1532 	if (ser->type != PORT_UNKNOWN && ser->type != PORT_MPSC)
1533 		rc = -EINVAL;
1534 	else if (pi->port.irq != ser->irq)
1535 		rc = -EINVAL;
1536 	else if (ser->io_type != SERIAL_IO_MEM)
1537 		rc = -EINVAL;
1538 	else if (pi->port.uartclk / 16 != ser->baud_base) /* Not sure */
1539 		rc = -EINVAL;
1540 	else if ((void *)pi->port.mapbase != ser->iomem_base)
1541 		rc = -EINVAL;
1542 	else if (pi->port.iobase != ser->port)
1543 		rc = -EINVAL;
1544 	else if (ser->hub6 != 0)
1545 		rc = -EINVAL;
1546 
1547 	return rc;
1548 }
1549 #ifdef CONFIG_CONSOLE_POLL
1550 /* Serial polling routines for writing and reading from the uart while
1551  * in an interrupt or debug context.
1552  */
1553 
1554 static char poll_buf[2048];
1555 static int poll_ptr;
1556 static int poll_cnt;
1557 static void mpsc_put_poll_char(struct uart_port *port,
1558 							   unsigned char c);
1559 
mpsc_get_poll_char(struct uart_port * port)1560 static int mpsc_get_poll_char(struct uart_port *port)
1561 {
1562 	struct mpsc_port_info *pi =
1563 		container_of(port, struct mpsc_port_info, port);
1564 	struct mpsc_rx_desc *rxre;
1565 	u32	cmdstat, bytes_in, i;
1566 	u8	*bp;
1567 
1568 	if (!serial_polled)
1569 		serial_polled = 1;
1570 
1571 	pr_debug("mpsc_rx_intr[%d]: Handling Rx intr\n", pi->port.line);
1572 
1573 	if (poll_cnt) {
1574 		poll_cnt--;
1575 		return poll_buf[poll_ptr++];
1576 	}
1577 	poll_ptr = 0;
1578 	poll_cnt = 0;
1579 
1580 	while (poll_cnt == 0) {
1581 		rxre = (struct mpsc_rx_desc *)(pi->rxr +
1582 		       (pi->rxr_posn*MPSC_RXRE_SIZE));
1583 		dma_cache_sync(pi->port.dev, (void *)rxre,
1584 			       MPSC_RXRE_SIZE, DMA_FROM_DEVICE);
1585 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1586 		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1587 			invalidate_dcache_range((ulong)rxre,
1588 			(ulong)rxre + MPSC_RXRE_SIZE);
1589 #endif
1590 		/*
1591 		 * Loop through Rx descriptors handling ones that have
1592 		 * been completed.
1593 		 */
1594 		while (poll_cnt == 0 &&
1595 		       !((cmdstat = be32_to_cpu(rxre->cmdstat)) &
1596 			 SDMA_DESC_CMDSTAT_O)){
1597 			bytes_in = be16_to_cpu(rxre->bytecnt);
1598 			bp = pi->rxb + (pi->rxr_posn * MPSC_RXBE_SIZE);
1599 			dma_cache_sync(pi->port.dev, (void *) bp,
1600 				       MPSC_RXBE_SIZE, DMA_FROM_DEVICE);
1601 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1602 			if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1603 				invalidate_dcache_range((ulong)bp,
1604 					(ulong)bp + MPSC_RXBE_SIZE);
1605 #endif
1606 			if ((unlikely(cmdstat & (SDMA_DESC_CMDSTAT_BR |
1607 			 SDMA_DESC_CMDSTAT_FR | SDMA_DESC_CMDSTAT_OR))) &&
1608 				!(cmdstat & pi->port.ignore_status_mask)) {
1609 				poll_buf[poll_cnt] = *bp;
1610 				poll_cnt++;
1611 			} else {
1612 				for (i = 0; i < bytes_in; i++) {
1613 					poll_buf[poll_cnt] = *bp++;
1614 					poll_cnt++;
1615 				}
1616 				pi->port.icount.rx += bytes_in;
1617 			}
1618 			rxre->bytecnt = cpu_to_be16(0);
1619 			wmb();
1620 			rxre->cmdstat = cpu_to_be32(SDMA_DESC_CMDSTAT_O |
1621 						    SDMA_DESC_CMDSTAT_EI |
1622 						    SDMA_DESC_CMDSTAT_F |
1623 						    SDMA_DESC_CMDSTAT_L);
1624 			wmb();
1625 			dma_cache_sync(pi->port.dev, (void *)rxre,
1626 				       MPSC_RXRE_SIZE, DMA_BIDIRECTIONAL);
1627 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1628 			if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1629 				flush_dcache_range((ulong)rxre,
1630 					   (ulong)rxre + MPSC_RXRE_SIZE);
1631 #endif
1632 
1633 			/* Advance to next descriptor */
1634 			pi->rxr_posn = (pi->rxr_posn + 1) &
1635 				(MPSC_RXR_ENTRIES - 1);
1636 			rxre = (struct mpsc_rx_desc *)(pi->rxr +
1637 				       (pi->rxr_posn * MPSC_RXRE_SIZE));
1638 			dma_cache_sync(pi->port.dev, (void *)rxre,
1639 				       MPSC_RXRE_SIZE, DMA_FROM_DEVICE);
1640 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1641 			if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1642 				invalidate_dcache_range((ulong)rxre,
1643 						(ulong)rxre + MPSC_RXRE_SIZE);
1644 #endif
1645 		}
1646 
1647 		/* Restart rx engine, if its stopped */
1648 		if ((readl(pi->sdma_base + SDMA_SDCM) & SDMA_SDCM_ERD) == 0)
1649 			mpsc_start_rx(pi);
1650 	}
1651 	if (poll_cnt) {
1652 		poll_cnt--;
1653 		return poll_buf[poll_ptr++];
1654 	}
1655 
1656 	return 0;
1657 }
1658 
1659 
mpsc_put_poll_char(struct uart_port * port,unsigned char c)1660 static void mpsc_put_poll_char(struct uart_port *port,
1661 			 unsigned char c)
1662 {
1663 	struct mpsc_port_info *pi =
1664 		container_of(port, struct mpsc_port_info, port);
1665 	u32 data;
1666 
1667 	data = readl(pi->mpsc_base + MPSC_MPCR);
1668 	writeb(c, pi->mpsc_base + MPSC_CHR_1);
1669 	mb();
1670 	data = readl(pi->mpsc_base + MPSC_CHR_2);
1671 	data |= MPSC_CHR_2_TTCS;
1672 	writel(data, pi->mpsc_base + MPSC_CHR_2);
1673 	mb();
1674 
1675 	while (readl(pi->mpsc_base + MPSC_CHR_2) & MPSC_CHR_2_TTCS);
1676 }
1677 #endif
1678 
1679 static struct uart_ops mpsc_pops = {
1680 	.tx_empty	= mpsc_tx_empty,
1681 	.set_mctrl	= mpsc_set_mctrl,
1682 	.get_mctrl	= mpsc_get_mctrl,
1683 	.stop_tx	= mpsc_stop_tx,
1684 	.start_tx	= mpsc_start_tx,
1685 	.stop_rx	= mpsc_stop_rx,
1686 	.break_ctl	= mpsc_break_ctl,
1687 	.startup	= mpsc_startup,
1688 	.shutdown	= mpsc_shutdown,
1689 	.set_termios	= mpsc_set_termios,
1690 	.type		= mpsc_type,
1691 	.release_port	= mpsc_release_port,
1692 	.request_port	= mpsc_request_port,
1693 	.config_port	= mpsc_config_port,
1694 	.verify_port	= mpsc_verify_port,
1695 #ifdef CONFIG_CONSOLE_POLL
1696 	.poll_get_char = mpsc_get_poll_char,
1697 	.poll_put_char = mpsc_put_poll_char,
1698 #endif
1699 };
1700 
1701 /*
1702  ******************************************************************************
1703  *
1704  * Console Interface Routines
1705  *
1706  ******************************************************************************
1707  */
1708 
1709 #ifdef CONFIG_SERIAL_MPSC_CONSOLE
mpsc_console_write(struct console * co,const char * s,uint count)1710 static void mpsc_console_write(struct console *co, const char *s, uint count)
1711 {
1712 	struct mpsc_port_info *pi = &mpsc_ports[co->index];
1713 	u8 *bp, *dp, add_cr = 0;
1714 	int i;
1715 	unsigned long iflags;
1716 
1717 	spin_lock_irqsave(&pi->tx_lock, iflags);
1718 
1719 	while (pi->txr_head != pi->txr_tail) {
1720 		while (mpsc_sdma_tx_active(pi))
1721 			udelay(100);
1722 		mpsc_sdma_intr_ack(pi);
1723 		mpsc_tx_intr(pi);
1724 	}
1725 
1726 	while (mpsc_sdma_tx_active(pi))
1727 		udelay(100);
1728 
1729 	while (count > 0) {
1730 		bp = dp = pi->txb + (pi->txr_head * MPSC_TXBE_SIZE);
1731 
1732 		for (i = 0; i < MPSC_TXBE_SIZE; i++) {
1733 			if (count == 0)
1734 				break;
1735 
1736 			if (add_cr) {
1737 				*(dp++) = '\r';
1738 				add_cr = 0;
1739 			} else {
1740 				*(dp++) = *s;
1741 
1742 				if (*(s++) == '\n') { /* add '\r' after '\n' */
1743 					add_cr = 1;
1744 					count++;
1745 				}
1746 			}
1747 
1748 			count--;
1749 		}
1750 
1751 		dma_cache_sync(pi->port.dev, (void *)bp, MPSC_TXBE_SIZE,
1752 				DMA_BIDIRECTIONAL);
1753 #if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
1754 		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
1755 			flush_dcache_range((ulong)bp,
1756 					(ulong)bp + MPSC_TXBE_SIZE);
1757 #endif
1758 		mpsc_setup_tx_desc(pi, i, 0);
1759 		pi->txr_head = (pi->txr_head + 1) & (MPSC_TXR_ENTRIES - 1);
1760 		mpsc_sdma_start_tx(pi);
1761 
1762 		while (mpsc_sdma_tx_active(pi))
1763 			udelay(100);
1764 
1765 		pi->txr_tail = (pi->txr_tail + 1) & (MPSC_TXR_ENTRIES - 1);
1766 	}
1767 
1768 	spin_unlock_irqrestore(&pi->tx_lock, iflags);
1769 }
1770 
mpsc_console_setup(struct console * co,char * options)1771 static int __init mpsc_console_setup(struct console *co, char *options)
1772 {
1773 	struct mpsc_port_info *pi;
1774 	int baud, bits, parity, flow;
1775 
1776 	pr_debug("mpsc_console_setup[%d]: options: %s\n", co->index, options);
1777 
1778 	if (co->index >= MPSC_NUM_CTLRS)
1779 		co->index = 0;
1780 
1781 	pi = &mpsc_ports[co->index];
1782 
1783 	baud = pi->default_baud;
1784 	bits = pi->default_bits;
1785 	parity = pi->default_parity;
1786 	flow = pi->default_flow;
1787 
1788 	if (!pi->port.ops)
1789 		return -ENODEV;
1790 
1791 	spin_lock_init(&pi->port.lock);	/* Temporary fix--copied from 8250.c */
1792 
1793 	if (options)
1794 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1795 
1796 	return uart_set_options(&pi->port, co, baud, parity, bits, flow);
1797 }
1798 
1799 static struct console mpsc_console = {
1800 	.name	= MPSC_DEV_NAME,
1801 	.write	= mpsc_console_write,
1802 	.device	= uart_console_device,
1803 	.setup	= mpsc_console_setup,
1804 	.flags	= CON_PRINTBUFFER,
1805 	.index	= -1,
1806 	.data	= &mpsc_reg,
1807 };
1808 
mpsc_late_console_init(void)1809 static int __init mpsc_late_console_init(void)
1810 {
1811 	pr_debug("mpsc_late_console_init: Enter\n");
1812 
1813 	if (!(mpsc_console.flags & CON_ENABLED))
1814 		register_console(&mpsc_console);
1815 	return 0;
1816 }
1817 
1818 late_initcall(mpsc_late_console_init);
1819 
1820 #define MPSC_CONSOLE	&mpsc_console
1821 #else
1822 #define MPSC_CONSOLE	NULL
1823 #endif
1824 /*
1825  ******************************************************************************
1826  *
1827  * Dummy Platform Driver to extract & map shared register regions
1828  *
1829  ******************************************************************************
1830  */
mpsc_resource_err(char * s)1831 static void mpsc_resource_err(char *s)
1832 {
1833 	printk(KERN_WARNING "MPSC: Platform device resource error in %s\n", s);
1834 }
1835 
mpsc_shared_map_regs(struct platform_device * pd)1836 static int mpsc_shared_map_regs(struct platform_device *pd)
1837 {
1838 	struct resource	*r;
1839 
1840 	if ((r = platform_get_resource(pd, IORESOURCE_MEM,
1841 					MPSC_ROUTING_BASE_ORDER))
1842 			&& request_mem_region(r->start,
1843 				MPSC_ROUTING_REG_BLOCK_SIZE,
1844 				"mpsc_routing_regs")) {
1845 		mpsc_shared_regs.mpsc_routing_base = ioremap(r->start,
1846 				MPSC_ROUTING_REG_BLOCK_SIZE);
1847 		mpsc_shared_regs.mpsc_routing_base_p = r->start;
1848 	} else {
1849 		mpsc_resource_err("MPSC routing base");
1850 		return -ENOMEM;
1851 	}
1852 
1853 	if ((r = platform_get_resource(pd, IORESOURCE_MEM,
1854 					MPSC_SDMA_INTR_BASE_ORDER))
1855 			&& request_mem_region(r->start,
1856 				MPSC_SDMA_INTR_REG_BLOCK_SIZE,
1857 				"sdma_intr_regs")) {
1858 		mpsc_shared_regs.sdma_intr_base = ioremap(r->start,
1859 			MPSC_SDMA_INTR_REG_BLOCK_SIZE);
1860 		mpsc_shared_regs.sdma_intr_base_p = r->start;
1861 	} else {
1862 		iounmap(mpsc_shared_regs.mpsc_routing_base);
1863 		release_mem_region(mpsc_shared_regs.mpsc_routing_base_p,
1864 				MPSC_ROUTING_REG_BLOCK_SIZE);
1865 		mpsc_resource_err("SDMA intr base");
1866 		return -ENOMEM;
1867 	}
1868 
1869 	return 0;
1870 }
1871 
mpsc_shared_unmap_regs(void)1872 static void mpsc_shared_unmap_regs(void)
1873 {
1874 	if (!mpsc_shared_regs.mpsc_routing_base) {
1875 		iounmap(mpsc_shared_regs.mpsc_routing_base);
1876 		release_mem_region(mpsc_shared_regs.mpsc_routing_base_p,
1877 				MPSC_ROUTING_REG_BLOCK_SIZE);
1878 	}
1879 	if (!mpsc_shared_regs.sdma_intr_base) {
1880 		iounmap(mpsc_shared_regs.sdma_intr_base);
1881 		release_mem_region(mpsc_shared_regs.sdma_intr_base_p,
1882 				MPSC_SDMA_INTR_REG_BLOCK_SIZE);
1883 	}
1884 
1885 	mpsc_shared_regs.mpsc_routing_base = NULL;
1886 	mpsc_shared_regs.sdma_intr_base = NULL;
1887 
1888 	mpsc_shared_regs.mpsc_routing_base_p = 0;
1889 	mpsc_shared_regs.sdma_intr_base_p = 0;
1890 }
1891 
mpsc_shared_drv_probe(struct platform_device * dev)1892 static int mpsc_shared_drv_probe(struct platform_device *dev)
1893 {
1894 	struct mpsc_shared_pdata	*pdata;
1895 	int				 rc = -ENODEV;
1896 
1897 	if (dev->id == 0) {
1898 		if (!(rc = mpsc_shared_map_regs(dev))) {
1899 			pdata = (struct mpsc_shared_pdata *)
1900 				dev_get_platdata(&dev->dev);
1901 
1902 			mpsc_shared_regs.MPSC_MRR_m = pdata->mrr_val;
1903 			mpsc_shared_regs.MPSC_RCRR_m= pdata->rcrr_val;
1904 			mpsc_shared_regs.MPSC_TCRR_m= pdata->tcrr_val;
1905 			mpsc_shared_regs.SDMA_INTR_CAUSE_m =
1906 				pdata->intr_cause_val;
1907 			mpsc_shared_regs.SDMA_INTR_MASK_m =
1908 				pdata->intr_mask_val;
1909 
1910 			rc = 0;
1911 		}
1912 	}
1913 
1914 	return rc;
1915 }
1916 
mpsc_shared_drv_remove(struct platform_device * dev)1917 static int mpsc_shared_drv_remove(struct platform_device *dev)
1918 {
1919 	int	rc = -ENODEV;
1920 
1921 	if (dev->id == 0) {
1922 		mpsc_shared_unmap_regs();
1923 		mpsc_shared_regs.MPSC_MRR_m = 0;
1924 		mpsc_shared_regs.MPSC_RCRR_m = 0;
1925 		mpsc_shared_regs.MPSC_TCRR_m = 0;
1926 		mpsc_shared_regs.SDMA_INTR_CAUSE_m = 0;
1927 		mpsc_shared_regs.SDMA_INTR_MASK_m = 0;
1928 		rc = 0;
1929 	}
1930 
1931 	return rc;
1932 }
1933 
1934 static struct platform_driver mpsc_shared_driver = {
1935 	.probe	= mpsc_shared_drv_probe,
1936 	.remove	= mpsc_shared_drv_remove,
1937 	.driver	= {
1938 		.name	= MPSC_SHARED_NAME,
1939 	},
1940 };
1941 
1942 /*
1943  ******************************************************************************
1944  *
1945  * Driver Interface Routines
1946  *
1947  ******************************************************************************
1948  */
1949 static struct uart_driver mpsc_reg = {
1950 	.owner		= THIS_MODULE,
1951 	.driver_name	= MPSC_DRIVER_NAME,
1952 	.dev_name	= MPSC_DEV_NAME,
1953 	.major		= MPSC_MAJOR,
1954 	.minor		= MPSC_MINOR_START,
1955 	.nr		= MPSC_NUM_CTLRS,
1956 	.cons		= MPSC_CONSOLE,
1957 };
1958 
mpsc_drv_map_regs(struct mpsc_port_info * pi,struct platform_device * pd)1959 static int mpsc_drv_map_regs(struct mpsc_port_info *pi,
1960 		struct platform_device *pd)
1961 {
1962 	struct resource	*r;
1963 
1964 	if ((r = platform_get_resource(pd, IORESOURCE_MEM, MPSC_BASE_ORDER))
1965 			&& request_mem_region(r->start, MPSC_REG_BLOCK_SIZE,
1966 			"mpsc_regs")) {
1967 		pi->mpsc_base = ioremap(r->start, MPSC_REG_BLOCK_SIZE);
1968 		pi->mpsc_base_p = r->start;
1969 	} else {
1970 		mpsc_resource_err("MPSC base");
1971 		goto err;
1972 	}
1973 
1974 	if ((r = platform_get_resource(pd, IORESOURCE_MEM,
1975 					MPSC_SDMA_BASE_ORDER))
1976 			&& request_mem_region(r->start,
1977 				MPSC_SDMA_REG_BLOCK_SIZE, "sdma_regs")) {
1978 		pi->sdma_base = ioremap(r->start,MPSC_SDMA_REG_BLOCK_SIZE);
1979 		pi->sdma_base_p = r->start;
1980 	} else {
1981 		mpsc_resource_err("SDMA base");
1982 		if (pi->mpsc_base) {
1983 			iounmap(pi->mpsc_base);
1984 			pi->mpsc_base = NULL;
1985 		}
1986 		goto err;
1987 	}
1988 
1989 	if ((r = platform_get_resource(pd,IORESOURCE_MEM,MPSC_BRG_BASE_ORDER))
1990 			&& request_mem_region(r->start,
1991 				MPSC_BRG_REG_BLOCK_SIZE, "brg_regs")) {
1992 		pi->brg_base = ioremap(r->start, MPSC_BRG_REG_BLOCK_SIZE);
1993 		pi->brg_base_p = r->start;
1994 	} else {
1995 		mpsc_resource_err("BRG base");
1996 		if (pi->mpsc_base) {
1997 			iounmap(pi->mpsc_base);
1998 			pi->mpsc_base = NULL;
1999 		}
2000 		if (pi->sdma_base) {
2001 			iounmap(pi->sdma_base);
2002 			pi->sdma_base = NULL;
2003 		}
2004 		goto err;
2005 	}
2006 	return 0;
2007 
2008 err:
2009 	return -ENOMEM;
2010 }
2011 
mpsc_drv_unmap_regs(struct mpsc_port_info * pi)2012 static void mpsc_drv_unmap_regs(struct mpsc_port_info *pi)
2013 {
2014 	if (!pi->mpsc_base) {
2015 		iounmap(pi->mpsc_base);
2016 		release_mem_region(pi->mpsc_base_p, MPSC_REG_BLOCK_SIZE);
2017 	}
2018 	if (!pi->sdma_base) {
2019 		iounmap(pi->sdma_base);
2020 		release_mem_region(pi->sdma_base_p, MPSC_SDMA_REG_BLOCK_SIZE);
2021 	}
2022 	if (!pi->brg_base) {
2023 		iounmap(pi->brg_base);
2024 		release_mem_region(pi->brg_base_p, MPSC_BRG_REG_BLOCK_SIZE);
2025 	}
2026 
2027 	pi->mpsc_base = NULL;
2028 	pi->sdma_base = NULL;
2029 	pi->brg_base = NULL;
2030 
2031 	pi->mpsc_base_p = 0;
2032 	pi->sdma_base_p = 0;
2033 	pi->brg_base_p = 0;
2034 }
2035 
mpsc_drv_get_platform_data(struct mpsc_port_info * pi,struct platform_device * pd,int num)2036 static void mpsc_drv_get_platform_data(struct mpsc_port_info *pi,
2037 		struct platform_device *pd, int num)
2038 {
2039 	struct mpsc_pdata	*pdata;
2040 
2041 	pdata = dev_get_platdata(&pd->dev);
2042 
2043 	pi->port.uartclk = pdata->brg_clk_freq;
2044 	pi->port.iotype = UPIO_MEM;
2045 	pi->port.line = num;
2046 	pi->port.type = PORT_MPSC;
2047 	pi->port.fifosize = MPSC_TXBE_SIZE;
2048 	pi->port.membase = pi->mpsc_base;
2049 	pi->port.mapbase = (ulong)pi->mpsc_base;
2050 	pi->port.ops = &mpsc_pops;
2051 
2052 	pi->mirror_regs = pdata->mirror_regs;
2053 	pi->cache_mgmt = pdata->cache_mgmt;
2054 	pi->brg_can_tune = pdata->brg_can_tune;
2055 	pi->brg_clk_src = pdata->brg_clk_src;
2056 	pi->mpsc_max_idle = pdata->max_idle;
2057 	pi->default_baud = pdata->default_baud;
2058 	pi->default_bits = pdata->default_bits;
2059 	pi->default_parity = pdata->default_parity;
2060 	pi->default_flow = pdata->default_flow;
2061 
2062 	/* Initial values of mirrored regs */
2063 	pi->MPSC_CHR_1_m = pdata->chr_1_val;
2064 	pi->MPSC_CHR_2_m = pdata->chr_2_val;
2065 	pi->MPSC_CHR_10_m = pdata->chr_10_val;
2066 	pi->MPSC_MPCR_m = pdata->mpcr_val;
2067 	pi->BRG_BCR_m = pdata->bcr_val;
2068 
2069 	pi->shared_regs = &mpsc_shared_regs;
2070 
2071 	pi->port.irq = platform_get_irq(pd, 0);
2072 }
2073 
mpsc_drv_probe(struct platform_device * dev)2074 static int mpsc_drv_probe(struct platform_device *dev)
2075 {
2076 	struct mpsc_port_info	*pi;
2077 	int			rc = -ENODEV;
2078 
2079 	pr_debug("mpsc_drv_probe: Adding MPSC %d\n", dev->id);
2080 
2081 	if (dev->id < MPSC_NUM_CTLRS) {
2082 		pi = &mpsc_ports[dev->id];
2083 
2084 		if (!(rc = mpsc_drv_map_regs(pi, dev))) {
2085 			mpsc_drv_get_platform_data(pi, dev, dev->id);
2086 			pi->port.dev = &dev->dev;
2087 
2088 			if (!(rc = mpsc_make_ready(pi))) {
2089 				spin_lock_init(&pi->tx_lock);
2090 				if (!(rc = uart_add_one_port(&mpsc_reg,
2091 								&pi->port))) {
2092 					rc = 0;
2093 				} else {
2094 					mpsc_release_port((struct uart_port *)
2095 							pi);
2096 					mpsc_drv_unmap_regs(pi);
2097 				}
2098 			} else {
2099 				mpsc_drv_unmap_regs(pi);
2100 			}
2101 		}
2102 	}
2103 
2104 	return rc;
2105 }
2106 
mpsc_drv_remove(struct platform_device * dev)2107 static int mpsc_drv_remove(struct platform_device *dev)
2108 {
2109 	pr_debug("mpsc_drv_exit: Removing MPSC %d\n", dev->id);
2110 
2111 	if (dev->id < MPSC_NUM_CTLRS) {
2112 		uart_remove_one_port(&mpsc_reg, &mpsc_ports[dev->id].port);
2113 		mpsc_release_port((struct uart_port *)
2114 				&mpsc_ports[dev->id].port);
2115 		mpsc_drv_unmap_regs(&mpsc_ports[dev->id]);
2116 		return 0;
2117 	} else {
2118 		return -ENODEV;
2119 	}
2120 }
2121 
2122 static struct platform_driver mpsc_driver = {
2123 	.probe	= mpsc_drv_probe,
2124 	.remove	= mpsc_drv_remove,
2125 	.driver	= {
2126 		.name	= MPSC_CTLR_NAME,
2127 	},
2128 };
2129 
mpsc_drv_init(void)2130 static int __init mpsc_drv_init(void)
2131 {
2132 	int	rc;
2133 
2134 	printk(KERN_INFO "Serial: MPSC driver\n");
2135 
2136 	memset(mpsc_ports, 0, sizeof(mpsc_ports));
2137 	memset(&mpsc_shared_regs, 0, sizeof(mpsc_shared_regs));
2138 
2139 	if (!(rc = uart_register_driver(&mpsc_reg))) {
2140 		if (!(rc = platform_driver_register(&mpsc_shared_driver))) {
2141 			if ((rc = platform_driver_register(&mpsc_driver))) {
2142 				platform_driver_unregister(&mpsc_shared_driver);
2143 				uart_unregister_driver(&mpsc_reg);
2144 			}
2145 		} else {
2146 			uart_unregister_driver(&mpsc_reg);
2147 		}
2148 	}
2149 
2150 	return rc;
2151 }
2152 
mpsc_drv_exit(void)2153 static void __exit mpsc_drv_exit(void)
2154 {
2155 	platform_driver_unregister(&mpsc_driver);
2156 	platform_driver_unregister(&mpsc_shared_driver);
2157 	uart_unregister_driver(&mpsc_reg);
2158 	memset(mpsc_ports, 0, sizeof(mpsc_ports));
2159 	memset(&mpsc_shared_regs, 0, sizeof(mpsc_shared_regs));
2160 }
2161 
2162 module_init(mpsc_drv_init);
2163 module_exit(mpsc_drv_exit);
2164 
2165 MODULE_AUTHOR("Mark A. Greer <mgreer@mvista.com>");
2166 MODULE_DESCRIPTION("Generic Marvell MPSC serial/UART driver");
2167 MODULE_VERSION(MPSC_VERSION);
2168 MODULE_LICENSE("GPL");
2169 MODULE_ALIAS_CHARDEV_MAJOR(MPSC_MAJOR);
2170 MODULE_ALIAS("platform:" MPSC_CTLR_NAME);
2171