Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hskinnemoen...
[linux-2.6] / arch / sparc64 / kernel / chmc.c
1 /* memctrlr.c: Driver for UltraSPARC-III memory controller.
2  *
3  * Copyright (C) 2001, 2007 David S. Miller (davem@davemloft.net)
4  */
5
6 #include <linux/module.h>
7 #include <linux/kernel.h>
8 #include <linux/types.h>
9 #include <linux/slab.h>
10 #include <linux/list.h>
11 #include <linux/string.h>
12 #include <linux/sched.h>
13 #include <linux/smp.h>
14 #include <linux/errno.h>
15 #include <linux/init.h>
16 #include <asm/spitfire.h>
17 #include <asm/chmctrl.h>
18 #include <asm/cpudata.h>
19 #include <asm/oplib.h>
20 #include <asm/prom.h>
21 #include <asm/io.h>
22
23 #define CHMCTRL_NDGRPS  2
24 #define CHMCTRL_NDIMMS  4
25
26 #define DIMMS_PER_MC    (CHMCTRL_NDGRPS * CHMCTRL_NDIMMS)
27
28 /* OBP memory-layout property format. */
29 struct obp_map {
30         unsigned char   dimm_map[144];
31         unsigned char   pin_map[576];
32 };
33
34 #define DIMM_LABEL_SZ   8
35
36 struct obp_mem_layout {
37         /* One max 8-byte string label per DIMM.  Usually
38          * this matches the label on the motherboard where
39          * that DIMM resides.
40          */
41         char            dimm_labels[DIMMS_PER_MC][DIMM_LABEL_SZ];
42
43         /* If symmetric use map[0], else it is
44          * asymmetric and map[1] should be used.
45          */
46         char            symmetric;
47
48         struct obp_map  map[2];
49 };
50
51 #define CHMCTRL_NBANKS  4
52
53 struct bank_info {
54         struct mctrl_info       *mp;
55         int                     bank_id;
56
57         u64                     raw_reg;
58         int                     valid;
59         int                     uk;
60         int                     um;
61         int                     lk;
62         int                     lm;
63         int                     interleave;
64         unsigned long           base;
65         unsigned long           size;
66 };
67
68 struct mctrl_info {
69         struct list_head        list;
70         int                     portid;
71
72         struct obp_mem_layout   layout_prop;
73         int                     layout_size;
74
75         void __iomem            *regs;
76
77         u64                     timing_control1;
78         u64                     timing_control2;
79         u64                     timing_control3;
80         u64                     timing_control4;
81         u64                     memaddr_control;
82
83         struct bank_info        logical_banks[CHMCTRL_NBANKS];
84 };
85
86 static LIST_HEAD(mctrl_list);
87
88 /* Does BANK decode PHYS_ADDR? */
89 static int bank_match(struct bank_info *bp, unsigned long phys_addr)
90 {
91         unsigned long upper_bits = (phys_addr & PA_UPPER_BITS) >> PA_UPPER_BITS_SHIFT;
92         unsigned long lower_bits = (phys_addr & PA_LOWER_BITS) >> PA_LOWER_BITS_SHIFT;
93
94         /* Bank must be enabled to match. */
95         if (bp->valid == 0)
96                 return 0;
97
98         /* Would BANK match upper bits? */
99         upper_bits ^= bp->um;           /* What bits are different? */
100         upper_bits  = ~upper_bits;      /* Invert. */
101         upper_bits |= bp->uk;           /* What bits don't matter for matching? */
102         upper_bits  = ~upper_bits;      /* Invert. */
103
104         if (upper_bits)
105                 return 0;
106
107         /* Would BANK match lower bits? */
108         lower_bits ^= bp->lm;           /* What bits are different? */
109         lower_bits  = ~lower_bits;      /* Invert. */
110         lower_bits |= bp->lk;           /* What bits don't matter for matching? */
111         lower_bits  = ~lower_bits;      /* Invert. */
112
113         if (lower_bits)
114                 return 0;
115
116         /* I always knew you'd be the one. */
117         return 1;
118 }
119
120 /* Given PHYS_ADDR, search memory controller banks for a match. */
121 static struct bank_info *find_bank(unsigned long phys_addr)
122 {
123         struct list_head *mctrl_head = &mctrl_list;
124         struct list_head *mctrl_entry = mctrl_head->next;
125
126         for (;;) {
127                 struct mctrl_info *mp =
128                         list_entry(mctrl_entry, struct mctrl_info, list);
129                 int bank_no;
130
131                 if (mctrl_entry == mctrl_head)
132                         break;
133                 mctrl_entry = mctrl_entry->next;
134
135                 for (bank_no = 0; bank_no < CHMCTRL_NBANKS; bank_no++) {
136                         struct bank_info *bp;
137
138                         bp = &mp->logical_banks[bank_no];
139                         if (bank_match(bp, phys_addr))
140                                 return bp;
141                 }
142         }
143
144         return NULL;
145 }
146
147 /* This is the main purpose of this driver. */
148 #define SYNDROME_MIN    -1
149 #define SYNDROME_MAX    144
150 int chmc_getunumber(int syndrome_code,
151                     unsigned long phys_addr,
152                     char *buf, int buflen)
153 {
154         struct bank_info *bp;
155         struct obp_mem_layout *prop;
156         int bank_in_controller, first_dimm;
157
158         bp = find_bank(phys_addr);
159         if (bp == NULL ||
160             syndrome_code < SYNDROME_MIN ||
161             syndrome_code > SYNDROME_MAX) {
162                 buf[0] = '?';
163                 buf[1] = '?';
164                 buf[2] = '?';
165                 buf[3] = '\0';
166                 return 0;
167         }
168
169         prop = &bp->mp->layout_prop;
170         bank_in_controller = bp->bank_id & (CHMCTRL_NBANKS - 1);
171         first_dimm  = (bank_in_controller & (CHMCTRL_NDGRPS - 1));
172         first_dimm *= CHMCTRL_NDIMMS;
173
174         if (syndrome_code != SYNDROME_MIN) {
175                 struct obp_map *map;
176                 int qword, where_in_line, where, map_index, map_offset;
177                 unsigned int map_val;
178
179                 /* Yaay, single bit error so we can figure out
180                  * the exact dimm.
181                  */
182                 if (prop->symmetric)
183                         map = &prop->map[0];
184                 else
185                         map = &prop->map[1];
186
187                 /* Covert syndrome code into the way the bits are
188                  * positioned on the bus.
189                  */
190                 if (syndrome_code < 144 - 16)
191                         syndrome_code += 16;
192                 else if (syndrome_code < 144)
193                         syndrome_code -= (144 - 7);
194                 else if (syndrome_code < (144 + 3))
195                         syndrome_code -= (144 + 3 - 4);
196                 else
197                         syndrome_code -= 144 + 3;
198
199                 /* All this magic has to do with how a cache line
200                  * comes over the wire on Safari.  A 64-bit line
201                  * comes over in 4 quadword cycles, each of which
202                  * transmit ECC/MTAG info as well as the actual
203                  * data.  144 bits per quadword, 576 total.
204                  */
205 #define LINE_SIZE       64
206 #define LINE_ADDR_MSK   (LINE_SIZE - 1)
207 #define QW_PER_LINE     4
208 #define QW_BYTES        (LINE_SIZE / QW_PER_LINE)
209 #define QW_BITS         144
210 #define LAST_BIT        (576 - 1)
211
212                 qword = (phys_addr & LINE_ADDR_MSK) / QW_BYTES;
213                 where_in_line = ((3 - qword) * QW_BITS) + syndrome_code;
214                 where = (LAST_BIT - where_in_line);
215                 map_index = where >> 2;
216                 map_offset = where & 0x3;
217                 map_val = map->dimm_map[map_index];
218                 map_val = ((map_val >> ((3 - map_offset) << 1)) & (2 - 1));
219
220                 sprintf(buf, "%s, pin %3d",
221                         prop->dimm_labels[first_dimm + map_val],
222                         map->pin_map[where_in_line]);
223         } else {
224                 int dimm;
225
226                 /* Multi-bit error, we just dump out all the
227                  * dimm labels associated with this bank.
228                  */
229                 for (dimm = 0; dimm < CHMCTRL_NDIMMS; dimm++) {
230                         sprintf(buf, "%s ",
231                                 prop->dimm_labels[first_dimm + dimm]);
232                         buf += strlen(buf);
233                 }
234         }
235         return 0;
236 }
237
238 /* Accessing the registers is slightly complicated.  If you want
239  * to get at the memory controller which is on the same processor
240  * the code is executing, you must use special ASI load/store else
241  * you go through the global mapping.
242  */
243 static u64 read_mcreg(struct mctrl_info *mp, unsigned long offset)
244 {
245         unsigned long ret, this_cpu;
246
247         preempt_disable();
248
249         this_cpu = real_hard_smp_processor_id();
250
251         if (mp->portid == this_cpu) {
252                 __asm__ __volatile__("ldxa      [%1] %2, %0"
253                                      : "=r" (ret)
254                                      : "r" (offset), "i" (ASI_MCU_CTRL_REG));
255         } else {
256                 __asm__ __volatile__("ldxa      [%1] %2, %0"
257                                      : "=r" (ret)
258                                      : "r" (mp->regs + offset),
259                                        "i" (ASI_PHYS_BYPASS_EC_E));
260         }
261
262         preempt_enable();
263
264         return ret;
265 }
266
267 #if 0 /* currently unused */
268 static void write_mcreg(struct mctrl_info *mp, unsigned long offset, u64 val)
269 {
270         if (mp->portid == smp_processor_id()) {
271                 __asm__ __volatile__("stxa      %0, [%1] %2"
272                                      : : "r" (val),
273                                          "r" (offset), "i" (ASI_MCU_CTRL_REG));
274         } else {
275                 __asm__ __volatile__("ldxa      %0, [%1] %2"
276                                      : : "r" (val),
277                                          "r" (mp->regs + offset),
278                                          "i" (ASI_PHYS_BYPASS_EC_E));
279         }
280 }
281 #endif
282
283 static void interpret_one_decode_reg(struct mctrl_info *mp, int which_bank, u64 val)
284 {
285         struct bank_info *p = &mp->logical_banks[which_bank];
286
287         p->mp = mp;
288         p->bank_id = (CHMCTRL_NBANKS * mp->portid) + which_bank;
289         p->raw_reg = val;
290         p->valid = (val & MEM_DECODE_VALID) >> MEM_DECODE_VALID_SHIFT;
291         p->uk = (val & MEM_DECODE_UK) >> MEM_DECODE_UK_SHIFT;
292         p->um = (val & MEM_DECODE_UM) >> MEM_DECODE_UM_SHIFT;
293         p->lk = (val & MEM_DECODE_LK) >> MEM_DECODE_LK_SHIFT;
294         p->lm = (val & MEM_DECODE_LM) >> MEM_DECODE_LM_SHIFT;
295
296         p->base  =  (p->um);
297         p->base &= ~(p->uk);
298         p->base <<= PA_UPPER_BITS_SHIFT;
299
300         switch(p->lk) {
301         case 0xf:
302         default:
303                 p->interleave = 1;
304                 break;
305
306         case 0xe:
307                 p->interleave = 2;
308                 break;
309
310         case 0xc:
311                 p->interleave = 4;
312                 break;
313
314         case 0x8:
315                 p->interleave = 8;
316                 break;
317
318         case 0x0:
319                 p->interleave = 16;
320                 break;
321         };
322
323         /* UK[10] is reserved, and UK[11] is not set for the SDRAM
324          * bank size definition.
325          */
326         p->size = (((unsigned long)p->uk &
327                     ((1UL << 10UL) - 1UL)) + 1UL) << PA_UPPER_BITS_SHIFT;
328         p->size /= p->interleave;
329 }
330
331 static void fetch_decode_regs(struct mctrl_info *mp)
332 {
333         if (mp->layout_size == 0)
334                 return;
335
336         interpret_one_decode_reg(mp, 0,
337                                  read_mcreg(mp, CHMCTRL_DECODE1));
338         interpret_one_decode_reg(mp, 1,
339                                  read_mcreg(mp, CHMCTRL_DECODE2));
340         interpret_one_decode_reg(mp, 2,
341                                  read_mcreg(mp, CHMCTRL_DECODE3));
342         interpret_one_decode_reg(mp, 3,
343                                  read_mcreg(mp, CHMCTRL_DECODE4));
344 }
345
346 static int init_one_mctrl(struct device_node *dp)
347 {
348         struct mctrl_info *mp = kzalloc(sizeof(*mp), GFP_KERNEL);
349         int portid = of_getintprop_default(dp, "portid", -1);
350         const struct linux_prom64_registers *regs;
351         const void *pval;
352         int len;
353
354         if (!mp)
355                 return -1;
356         if (portid == -1)
357                 goto fail;
358
359         mp->portid = portid;
360         pval = of_get_property(dp, "memory-layout", &len);
361         mp->layout_size = len;
362         if (!pval)
363                 mp->layout_size = 0;
364         else {
365                 if (mp->layout_size > sizeof(mp->layout_prop))
366                         goto fail;
367                 memcpy(&mp->layout_prop, pval, len);
368         }
369
370         regs = of_get_property(dp, "reg", NULL);
371         if (!regs || regs->reg_size != 0x48)
372                 goto fail;
373
374         mp->regs = ioremap(regs->phys_addr, regs->reg_size);
375         if (mp->regs == NULL)
376                 goto fail;
377
378         if (mp->layout_size != 0UL) {
379                 mp->timing_control1 = read_mcreg(mp, CHMCTRL_TCTRL1);
380                 mp->timing_control2 = read_mcreg(mp, CHMCTRL_TCTRL2);
381                 mp->timing_control3 = read_mcreg(mp, CHMCTRL_TCTRL3);
382                 mp->timing_control4 = read_mcreg(mp, CHMCTRL_TCTRL4);
383                 mp->memaddr_control = read_mcreg(mp, CHMCTRL_MACTRL);
384         }
385
386         fetch_decode_regs(mp);
387
388         list_add(&mp->list, &mctrl_list);
389
390         /* Report the device. */
391         printk(KERN_INFO "%s: US3 memory controller at %p [%s]\n",
392                dp->full_name,
393                mp->regs, (mp->layout_size ? "ACTIVE" : "INACTIVE"));
394
395         return 0;
396
397 fail:
398         if (mp) {
399                 if (mp->regs != NULL)
400                         iounmap(mp->regs);
401                 kfree(mp);
402         }
403         return -1;
404 }
405
406 static int __init chmc_init(void)
407 {
408         struct device_node *dp;
409
410         /* This driver is only for cheetah platforms. */
411         if (tlb_type != cheetah && tlb_type != cheetah_plus)
412                 return -ENODEV;
413
414         for_each_node_by_name(dp, "memory-controller")
415                 init_one_mctrl(dp);
416
417         for_each_node_by_name(dp, "mc-us3")
418                 init_one_mctrl(dp);
419
420         return 0;
421 }
422
423 static void __exit chmc_cleanup(void)
424 {
425         struct list_head *head = &mctrl_list;
426         struct list_head *tmp = head->next;
427
428         for (;;) {
429                 struct mctrl_info *p =
430                         list_entry(tmp, struct mctrl_info, list);
431                 if (tmp == head)
432                         break;
433                 tmp = tmp->next;
434
435                 list_del(&p->list);
436                 iounmap(p->regs);
437                 kfree(p);
438         }
439 }
440
441 module_init(chmc_init);
442 module_exit(chmc_cleanup);