1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * (C) 2005, 2006 Red Hat Inc.
4 *
5 * Author: David Woodhouse <dwmw2@infradead.org>
6 * Tom Sylla <tom.sylla@amd.com>
7 *
8 * Overview:
9 * This is a device driver for the NAND flash controller found on
10 * the AMD CS5535/CS5536 companion chipsets for the Geode processor.
11 * mtd-id for command line partitioning is cs553x_nand_cs[0-3]
12 * where 0-3 reflects the chip select for NAND.
13 */
14
15 #include <linux/kernel.h>
16 #include <linux/slab.h>
17 #include <linux/init.h>
18 #include <linux/module.h>
19 #include <linux/delay.h>
20 #include <linux/mtd/mtd.h>
21 #include <linux/mtd/rawnand.h>
22 #include <linux/mtd/partitions.h>
23 #include <linux/iopoll.h>
24
25 #include <asm/msr.h>
26
27 #define NR_CS553X_CONTROLLERS 4
28
29 #define MSR_DIVIL_GLD_CAP 0x51400000 /* DIVIL capabilitiies */
30 #define CAP_CS5535 0x2df000ULL
31 #define CAP_CS5536 0x5df500ULL
32
33 /* NAND Timing MSRs */
34 #define MSR_NANDF_DATA 0x5140001b /* NAND Flash Data Timing MSR */
35 #define MSR_NANDF_CTL 0x5140001c /* NAND Flash Control Timing */
36 #define MSR_NANDF_RSVD 0x5140001d /* Reserved */
37
38 /* NAND BAR MSRs */
39 #define MSR_DIVIL_LBAR_FLSH0 0x51400010 /* Flash Chip Select 0 */
40 #define MSR_DIVIL_LBAR_FLSH1 0x51400011 /* Flash Chip Select 1 */
41 #define MSR_DIVIL_LBAR_FLSH2 0x51400012 /* Flash Chip Select 2 */
42 #define MSR_DIVIL_LBAR_FLSH3 0x51400013 /* Flash Chip Select 3 */
43 /* Each made up of... */
44 #define FLSH_LBAR_EN (1ULL<<32)
45 #define FLSH_NOR_NAND (1ULL<<33) /* 1 for NAND */
46 #define FLSH_MEM_IO (1ULL<<34) /* 1 for MMIO */
47 /* I/O BARs have BASE_ADDR in bits 15:4, IO_MASK in 47:36 */
48 /* MMIO BARs have BASE_ADDR in bits 31:12, MEM_MASK in 63:44 */
49
50 /* Pin function selection MSR (IDE vs. flash on the IDE pins) */
51 #define MSR_DIVIL_BALL_OPTS 0x51400015
52 #define PIN_OPT_IDE (1<<0) /* 0 for flash, 1 for IDE */
53
54 /* Registers within the NAND flash controller BAR -- memory mapped */
55 #define MM_NAND_DATA 0x00 /* 0 to 0x7ff, in fact */
56 #define MM_NAND_CTL 0x800 /* Any even address 0x800-0x80e */
57 #define MM_NAND_IO 0x801 /* Any odd address 0x801-0x80f */
58 #define MM_NAND_STS 0x810
59 #define MM_NAND_ECC_LSB 0x811
60 #define MM_NAND_ECC_MSB 0x812
61 #define MM_NAND_ECC_COL 0x813
62 #define MM_NAND_LAC 0x814
63 #define MM_NAND_ECC_CTL 0x815
64
65 /* Registers within the NAND flash controller BAR -- I/O mapped */
66 #define IO_NAND_DATA 0x00 /* 0 to 3, in fact */
67 #define IO_NAND_CTL 0x04
68 #define IO_NAND_IO 0x05
69 #define IO_NAND_STS 0x06
70 #define IO_NAND_ECC_CTL 0x08
71 #define IO_NAND_ECC_LSB 0x09
72 #define IO_NAND_ECC_MSB 0x0a
73 #define IO_NAND_ECC_COL 0x0b
74 #define IO_NAND_LAC 0x0c
75
76 #define CS_NAND_CTL_DIST_EN (1<<4) /* Enable NAND Distract interrupt */
77 #define CS_NAND_CTL_RDY_INT_MASK (1<<3) /* Enable RDY/BUSY# interrupt */
78 #define CS_NAND_CTL_ALE (1<<2)
79 #define CS_NAND_CTL_CLE (1<<1)
80 #define CS_NAND_CTL_CE (1<<0) /* Keep low; 1 to reset */
81
82 #define CS_NAND_STS_FLASH_RDY (1<<3)
83 #define CS_NAND_CTLR_BUSY (1<<2)
84 #define CS_NAND_CMD_COMP (1<<1)
85 #define CS_NAND_DIST_ST (1<<0)
86
87 #define CS_NAND_ECC_PARITY (1<<2)
88 #define CS_NAND_ECC_CLRECC (1<<1)
89 #define CS_NAND_ECC_ENECC (1<<0)
90
91 struct cs553x_nand_controller {
92 struct nand_controller base;
93 struct nand_chip chip;
94 void __iomem *mmio;
95 };
96
97 static struct cs553x_nand_controller *
to_cs553x(struct nand_controller * controller)98 to_cs553x(struct nand_controller *controller)
99 {
100 return container_of(controller, struct cs553x_nand_controller, base);
101 }
102
cs553x_write_ctrl_byte(struct cs553x_nand_controller * cs553x,u32 ctl,u8 data)103 static int cs553x_write_ctrl_byte(struct cs553x_nand_controller *cs553x,
104 u32 ctl, u8 data)
105 {
106 u8 status;
107 int ret;
108
109 writeb(ctl, cs553x->mmio + MM_NAND_CTL);
110 writeb(data, cs553x->mmio + MM_NAND_IO);
111 ret = readb_poll_timeout_atomic(cs553x->mmio + MM_NAND_STS, status,
112 !(status & CS_NAND_CTLR_BUSY), 1,
113 100000);
114 if (ret)
115 return ret;
116
117 return 0;
118 }
119
cs553x_data_in(struct cs553x_nand_controller * cs553x,void * buf,unsigned int len)120 static void cs553x_data_in(struct cs553x_nand_controller *cs553x, void *buf,
121 unsigned int len)
122 {
123 writeb(0, cs553x->mmio + MM_NAND_CTL);
124 while (unlikely(len > 0x800)) {
125 memcpy_fromio(buf, cs553x->mmio, 0x800);
126 buf += 0x800;
127 len -= 0x800;
128 }
129 memcpy_fromio(buf, cs553x->mmio, len);
130 }
131
cs553x_data_out(struct cs553x_nand_controller * cs553x,const void * buf,unsigned int len)132 static void cs553x_data_out(struct cs553x_nand_controller *cs553x,
133 const void *buf, unsigned int len)
134 {
135 writeb(0, cs553x->mmio + MM_NAND_CTL);
136 while (unlikely(len > 0x800)) {
137 memcpy_toio(cs553x->mmio, buf, 0x800);
138 buf += 0x800;
139 len -= 0x800;
140 }
141 memcpy_toio(cs553x->mmio, buf, len);
142 }
143
cs553x_wait_ready(struct cs553x_nand_controller * cs553x,unsigned int timeout_ms)144 static int cs553x_wait_ready(struct cs553x_nand_controller *cs553x,
145 unsigned int timeout_ms)
146 {
147 u8 mask = CS_NAND_CTLR_BUSY | CS_NAND_STS_FLASH_RDY;
148 u8 status;
149
150 return readb_poll_timeout(cs553x->mmio + MM_NAND_STS, status,
151 (status & mask) == CS_NAND_STS_FLASH_RDY, 100,
152 timeout_ms * 1000);
153 }
154
cs553x_exec_instr(struct cs553x_nand_controller * cs553x,const struct nand_op_instr * instr)155 static int cs553x_exec_instr(struct cs553x_nand_controller *cs553x,
156 const struct nand_op_instr *instr)
157 {
158 unsigned int i;
159 int ret = 0;
160
161 switch (instr->type) {
162 case NAND_OP_CMD_INSTR:
163 ret = cs553x_write_ctrl_byte(cs553x, CS_NAND_CTL_CLE,
164 instr->ctx.cmd.opcode);
165 break;
166
167 case NAND_OP_ADDR_INSTR:
168 for (i = 0; i < instr->ctx.addr.naddrs; i++) {
169 ret = cs553x_write_ctrl_byte(cs553x, CS_NAND_CTL_ALE,
170 instr->ctx.addr.addrs[i]);
171 if (ret)
172 break;
173 }
174 break;
175
176 case NAND_OP_DATA_IN_INSTR:
177 cs553x_data_in(cs553x, instr->ctx.data.buf.in,
178 instr->ctx.data.len);
179 break;
180
181 case NAND_OP_DATA_OUT_INSTR:
182 cs553x_data_out(cs553x, instr->ctx.data.buf.out,
183 instr->ctx.data.len);
184 break;
185
186 case NAND_OP_WAITRDY_INSTR:
187 ret = cs553x_wait_ready(cs553x, instr->ctx.waitrdy.timeout_ms);
188 break;
189 }
190
191 if (instr->delay_ns)
192 ndelay(instr->delay_ns);
193
194 return ret;
195 }
196
cs553x_exec_op(struct nand_chip * this,const struct nand_operation * op,bool check_only)197 static int cs553x_exec_op(struct nand_chip *this,
198 const struct nand_operation *op,
199 bool check_only)
200 {
201 struct cs553x_nand_controller *cs553x = to_cs553x(this->controller);
202 unsigned int i;
203 int ret;
204
205 if (check_only)
206 return true;
207
208 /* De-assert the CE pin */
209 writeb(0, cs553x->mmio + MM_NAND_CTL);
210 for (i = 0; i < op->ninstrs; i++) {
211 ret = cs553x_exec_instr(cs553x, &op->instrs[i]);
212 if (ret)
213 break;
214 }
215
216 /* Re-assert the CE pin. */
217 writeb(CS_NAND_CTL_CE, cs553x->mmio + MM_NAND_CTL);
218
219 return ret;
220 }
221
cs_enable_hwecc(struct nand_chip * this,int mode)222 static void cs_enable_hwecc(struct nand_chip *this, int mode)
223 {
224 struct cs553x_nand_controller *cs553x = to_cs553x(this->controller);
225
226 writeb(0x07, cs553x->mmio + MM_NAND_ECC_CTL);
227 }
228
cs_calculate_ecc(struct nand_chip * this,const u_char * dat,u_char * ecc_code)229 static int cs_calculate_ecc(struct nand_chip *this, const u_char *dat,
230 u_char *ecc_code)
231 {
232 struct cs553x_nand_controller *cs553x = to_cs553x(this->controller);
233 uint32_t ecc;
234
235 ecc = readl(cs553x->mmio + MM_NAND_STS);
236
237 ecc_code[1] = ecc >> 8;
238 ecc_code[0] = ecc >> 16;
239 ecc_code[2] = ecc >> 24;
240 return 0;
241 }
242
243 static struct cs553x_nand_controller *controllers[4];
244
cs553x_attach_chip(struct nand_chip * chip)245 static int cs553x_attach_chip(struct nand_chip *chip)
246 {
247 if (chip->ecc.engine_type != NAND_ECC_ENGINE_TYPE_ON_HOST)
248 return 0;
249
250 chip->ecc.size = 256;
251 chip->ecc.bytes = 3;
252 chip->ecc.hwctl = cs_enable_hwecc;
253 chip->ecc.calculate = cs_calculate_ecc;
254 chip->ecc.correct = rawnand_sw_hamming_correct;
255 chip->ecc.strength = 1;
256
257 return 0;
258 }
259
260 static const struct nand_controller_ops cs553x_nand_controller_ops = {
261 .exec_op = cs553x_exec_op,
262 .attach_chip = cs553x_attach_chip,
263 };
264
cs553x_init_one(int cs,int mmio,unsigned long adr)265 static int __init cs553x_init_one(int cs, int mmio, unsigned long adr)
266 {
267 struct cs553x_nand_controller *controller;
268 int err = 0;
269 struct nand_chip *this;
270 struct mtd_info *new_mtd;
271
272 pr_notice("Probing CS553x NAND controller CS#%d at %sIO 0x%08lx\n",
273 cs, mmio ? "MM" : "P", adr);
274
275 if (!mmio) {
276 pr_notice("PIO mode not yet implemented for CS553X NAND controller\n");
277 return -ENXIO;
278 }
279
280 /* Allocate memory for MTD device structure and private data */
281 controller = kzalloc(sizeof(*controller), GFP_KERNEL);
282 if (!controller) {
283 err = -ENOMEM;
284 goto out;
285 }
286
287 this = &controller->chip;
288 nand_controller_init(&controller->base);
289 controller->base.ops = &cs553x_nand_controller_ops;
290 this->controller = &controller->base;
291 new_mtd = nand_to_mtd(this);
292
293 /* Link the private data with the MTD structure */
294 new_mtd->owner = THIS_MODULE;
295
296 /* map physical address */
297 controller->mmio = ioremap(adr, 4096);
298 if (!controller->mmio) {
299 pr_warn("ioremap cs553x NAND @0x%08lx failed\n", adr);
300 err = -EIO;
301 goto out_mtd;
302 }
303
304 /* Enable the following for a flash based bad block table */
305 this->bbt_options = NAND_BBT_USE_FLASH;
306
307 new_mtd->name = kasprintf(GFP_KERNEL, "cs553x_nand_cs%d", cs);
308 if (!new_mtd->name) {
309 err = -ENOMEM;
310 goto out_ior;
311 }
312
313 /* Scan to find existence of the device */
314 err = nand_scan(this, 1);
315 if (err)
316 goto out_free;
317
318 controllers[cs] = controller;
319 goto out;
320
321 out_free:
322 kfree(new_mtd->name);
323 out_ior:
324 iounmap(controller->mmio);
325 out_mtd:
326 kfree(controller);
327 out:
328 return err;
329 }
330
is_geode(void)331 static int is_geode(void)
332 {
333 /* These are the CPUs which will have a CS553[56] companion chip */
334 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
335 boot_cpu_data.x86 == 5 &&
336 boot_cpu_data.x86_model == 10)
337 return 1; /* Geode LX */
338
339 if ((boot_cpu_data.x86_vendor == X86_VENDOR_NSC ||
340 boot_cpu_data.x86_vendor == X86_VENDOR_CYRIX) &&
341 boot_cpu_data.x86 == 5 &&
342 boot_cpu_data.x86_model == 5)
343 return 1; /* Geode GX (née GX2) */
344
345 return 0;
346 }
347
cs553x_init(void)348 static int __init cs553x_init(void)
349 {
350 int err = -ENXIO;
351 int i;
352 uint64_t val;
353
354 /* If the CPU isn't a Geode GX or LX, abort */
355 if (!is_geode())
356 return -ENXIO;
357
358 /* If it doesn't have the CS553[56], abort */
359 rdmsrl(MSR_DIVIL_GLD_CAP, val);
360 val &= ~0xFFULL;
361 if (val != CAP_CS5535 && val != CAP_CS5536)
362 return -ENXIO;
363
364 /* If it doesn't have the NAND controller enabled, abort */
365 rdmsrl(MSR_DIVIL_BALL_OPTS, val);
366 if (val & PIN_OPT_IDE) {
367 pr_info("CS553x NAND controller: Flash I/O not enabled in MSR_DIVIL_BALL_OPTS.\n");
368 return -ENXIO;
369 }
370
371 for (i = 0; i < NR_CS553X_CONTROLLERS; i++) {
372 rdmsrl(MSR_DIVIL_LBAR_FLSH0 + i, val);
373
374 if ((val & (FLSH_LBAR_EN|FLSH_NOR_NAND)) == (FLSH_LBAR_EN|FLSH_NOR_NAND))
375 err = cs553x_init_one(i, !!(val & FLSH_MEM_IO), val & 0xFFFFFFFF);
376 }
377
378 /* Register all devices together here. This means we can easily hack it to
379 do mtdconcat etc. if we want to. */
380 for (i = 0; i < NR_CS553X_CONTROLLERS; i++) {
381 if (controllers[i]) {
382 /* If any devices registered, return success. Else the last error. */
383 mtd_device_register(nand_to_mtd(&controllers[i]->chip),
384 NULL, 0);
385 err = 0;
386 }
387 }
388
389 return err;
390 }
391
392 module_init(cs553x_init);
393
cs553x_cleanup(void)394 static void __exit cs553x_cleanup(void)
395 {
396 int i;
397
398 for (i = 0; i < NR_CS553X_CONTROLLERS; i++) {
399 struct cs553x_nand_controller *controller = controllers[i];
400 struct nand_chip *this = &controller->chip;
401 struct mtd_info *mtd = nand_to_mtd(this);
402 int ret;
403
404 if (!mtd)
405 continue;
406
407 /* Release resources, unregister device */
408 ret = mtd_device_unregister(mtd);
409 WARN_ON(ret);
410 nand_cleanup(this);
411 kfree(mtd->name);
412 controllers[i] = NULL;
413
414 /* unmap physical address */
415 iounmap(controller->mmio);
416
417 /* Free the MTD device structure */
418 kfree(controller);
419 }
420 }
421
422 module_exit(cs553x_cleanup);
423
424 MODULE_LICENSE("GPL");
425 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
426 MODULE_DESCRIPTION("NAND controller driver for AMD CS5535/CS5536 companion chip");
427