x86: cleanup C1E enabled detection
[linux-2.6] / arch / x86 / kernel / cpu / amd.c
1 #include <linux/init.h>
2 #include <linux/bitops.h>
3 #include <linux/mm.h>
4 #include <asm/io.h>
5 #include <asm/processor.h>
6 #include <asm/apic.h>
7
8 #include <mach_apic.h>
9 #include "cpu.h"
10
11 /*
12  *      B step AMD K6 before B 9730xxxx have hardware bugs that can cause
13  *      misexecution of code under Linux. Owners of such processors should
14  *      contact AMD for precise details and a CPU swap.
15  *
16  *      See     http://www.multimania.com/poulot/k6bug.html
17  *              http://www.amd.com/K6/k6docs/revgd.html
18  *
19  *      The following test is erm.. interesting. AMD neglected to up
20  *      the chip setting when fixing the bug but they also tweaked some
21  *      performance at the same time..
22  */
23
24 extern void vide(void);
25 __asm__(".align 4\nvide: ret");
26
27 #ifdef CONFIG_X86_LOCAL_APIC
28 #define CPUID_PROCESSOR_SIGNATURE       1
29 #define CPUID_XFAM              0x0ff00000
30 #define CPUID_XFAM_K8           0x00000000
31 #define CPUID_XFAM_10H          0x00100000
32 #define CPUID_XFAM_11H          0x00200000
33 #define CPUID_XMOD              0x000f0000
34 #define CPUID_XMOD_REV_F        0x00040000
35
36 /* AMD systems with C1E don't have a working lAPIC timer. Check for that. */
37 static __cpuinit int amd_apic_timer_broken(void)
38 {
39         u32 lo, hi;
40         u32 eax = cpuid_eax(CPUID_PROCESSOR_SIGNATURE);
41         switch (eax & CPUID_XFAM) {
42         case CPUID_XFAM_K8:
43                 if ((eax & CPUID_XMOD) < CPUID_XMOD_REV_F)
44                         break;
45         case CPUID_XFAM_10H:
46         case CPUID_XFAM_11H:
47                 rdmsr(MSR_K8_INT_PENDING_MSG, lo, hi);
48                 if (lo & K8_INTP_C1E_ACTIVE_MASK) {
49                         if (smp_processor_id() != boot_cpu_physical_apicid)
50                                 printk(KERN_INFO "AMD C1E detected late. "
51                                        "        Force timer broadcast.\n");
52                         return 1;
53                 }
54                 break;
55         default:
56                 /* err on the side of caution */
57                 return 1;
58         }
59         return 0;
60 }
61 #endif
62
63 int force_mwait __cpuinitdata;
64
65 static void __cpuinit early_init_amd(struct cpuinfo_x86 *c)
66 {
67         if (cpuid_eax(0x80000000) >= 0x80000007) {
68                 c->x86_power = cpuid_edx(0x80000007);
69                 if (c->x86_power & (1<<8))
70                         set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
71         }
72 }
73
74 static void __cpuinit init_amd(struct cpuinfo_x86 *c)
75 {
76         u32 l, h;
77         int mbytes = num_physpages >> (20-PAGE_SHIFT);
78         int r;
79
80 #ifdef CONFIG_SMP
81         unsigned long long value;
82
83         /*
84          * Disable TLB flush filter by setting HWCR.FFDIS on K8
85          * bit 6 of msr C001_0015
86          *
87          * Errata 63 for SH-B3 steppings
88          * Errata 122 for all steppings (F+ have it disabled by default)
89          */
90         if (c->x86 == 15) {
91                 rdmsrl(MSR_K7_HWCR, value);
92                 value |= 1 << 6;
93                 wrmsrl(MSR_K7_HWCR, value);
94         }
95 #endif
96
97         early_init_amd(c);
98
99         /*
100          *      FIXME: We should handle the K5 here. Set up the write
101          *      range and also turn on MSR 83 bits 4 and 31 (write alloc,
102          *      no bus pipeline)
103          */
104
105         /*
106          * Bit 31 in normal CPUID used for nonstandard 3DNow ID;
107          * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
108          */
109         clear_cpu_cap(c, 0*32+31);
110
111         r = get_model_name(c);
112
113         switch (c->x86) {
114         case 4:
115                 /*
116                  * General Systems BIOSen alias the cpu frequency registers
117                  * of the Elan at 0x000df000. Unfortuantly, one of the Linux
118                  * drivers subsequently pokes it, and changes the CPU speed.
119                  * Workaround : Remove the unneeded alias.
120                  */
121 #define CBAR            (0xfffc) /* Configuration Base Address  (32-bit) */
122 #define CBAR_ENB        (0x80000000)
123 #define CBAR_KEY        (0X000000CB)
124                         if (c->x86_model == 9 || c->x86_model == 10) {
125                                 if (inl (CBAR) & CBAR_ENB)
126                                         outl (0 | CBAR_KEY, CBAR);
127                         }
128                         break;
129         case 5:
130                         if (c->x86_model < 6) {
131                                 /* Based on AMD doc 20734R - June 2000 */
132                                 if (c->x86_model == 0) {
133                                         clear_cpu_cap(c, X86_FEATURE_APIC);
134                                         set_cpu_cap(c, X86_FEATURE_PGE);
135                                 }
136                                 break;
137                         }
138
139                         if (c->x86_model == 6 && c->x86_mask == 1) {
140                                 const int K6_BUG_LOOP = 1000000;
141                                 int n;
142                                 void (*f_vide)(void);
143                                 unsigned long d, d2;
144
145                                 printk(KERN_INFO "AMD K6 stepping B detected - ");
146
147                                 /*
148                                  * It looks like AMD fixed the 2.6.2 bug and improved indirect
149                                  * calls at the same time.
150                                  */
151
152                                 n = K6_BUG_LOOP;
153                                 f_vide = vide;
154                                 rdtscl(d);
155                                 while (n--)
156                                         f_vide();
157                                 rdtscl(d2);
158                                 d = d2-d;
159
160                                 if (d > 20*K6_BUG_LOOP)
161                                         printk("system stability may be impaired when more than 32 MB are used.\n");
162                                 else
163                                         printk("probably OK (after B9730xxxx).\n");
164                                 printk(KERN_INFO "Please see http://membres.lycos.fr/poulot/k6bug.html\n");
165                         }
166
167                         /* K6 with old style WHCR */
168                         if (c->x86_model < 8 ||
169                            (c->x86_model == 8 && c->x86_mask < 8)) {
170                                 /* We can only write allocate on the low 508Mb */
171                                 if (mbytes > 508)
172                                         mbytes = 508;
173
174                                 rdmsr(MSR_K6_WHCR, l, h);
175                                 if ((l&0x0000FFFF) == 0) {
176                                         unsigned long flags;
177                                         l = (1<<0)|((mbytes/4)<<1);
178                                         local_irq_save(flags);
179                                         wbinvd();
180                                         wrmsr(MSR_K6_WHCR, l, h);
181                                         local_irq_restore(flags);
182                                         printk(KERN_INFO "Enabling old style K6 write allocation for %d Mb\n",
183                                                 mbytes);
184                                 }
185                                 break;
186                         }
187
188                         if ((c->x86_model == 8 && c->x86_mask > 7) ||
189                              c->x86_model == 9 || c->x86_model == 13) {
190                                 /* The more serious chips .. */
191
192                                 if (mbytes > 4092)
193                                         mbytes = 4092;
194
195                                 rdmsr(MSR_K6_WHCR, l, h);
196                                 if ((l&0xFFFF0000) == 0) {
197                                         unsigned long flags;
198                                         l = ((mbytes>>2)<<22)|(1<<16);
199                                         local_irq_save(flags);
200                                         wbinvd();
201                                         wrmsr(MSR_K6_WHCR, l, h);
202                                         local_irq_restore(flags);
203                                         printk(KERN_INFO "Enabling new style K6 write allocation for %d Mb\n",
204                                                 mbytes);
205                                 }
206
207                                 /*  Set MTRR capability flag if appropriate */
208                                 if (c->x86_model == 13 || c->x86_model == 9 ||
209                                    (c->x86_model == 8 && c->x86_mask >= 8))
210                                         set_cpu_cap(c, X86_FEATURE_K6_MTRR);
211                                 break;
212                         }
213
214                         if (c->x86_model == 10) {
215                                 /* AMD Geode LX is model 10 */
216                                 /* placeholder for any needed mods */
217                                 break;
218                         }
219                         break;
220         case 6: /* An Athlon/Duron */
221
222                         /*
223                          * Bit 15 of Athlon specific MSR 15, needs to be 0
224                          * to enable SSE on Palomino/Morgan/Barton CPU's.
225                          * If the BIOS didn't enable it already, enable it here.
226                          */
227                         if (c->x86_model >= 6 && c->x86_model <= 10) {
228                                 if (!cpu_has(c, X86_FEATURE_XMM)) {
229                                         printk(KERN_INFO "Enabling disabled K7/SSE Support.\n");
230                                         rdmsr(MSR_K7_HWCR, l, h);
231                                         l &= ~0x00008000;
232                                         wrmsr(MSR_K7_HWCR, l, h);
233                                         set_cpu_cap(c, X86_FEATURE_XMM);
234                                 }
235                         }
236
237                         /*
238                          * It's been determined by AMD that Athlons since model 8 stepping 1
239                          * are more robust with CLK_CTL set to 200xxxxx instead of 600xxxxx
240                          * As per AMD technical note 27212 0.2
241                          */
242                         if ((c->x86_model == 8 && c->x86_mask >= 1) || (c->x86_model > 8)) {
243                                 rdmsr(MSR_K7_CLK_CTL, l, h);
244                                 if ((l & 0xfff00000) != 0x20000000) {
245                                         printk ("CPU: CLK_CTL MSR was %x. Reprogramming to %x\n", l,
246                                                 ((l & 0x000fffff)|0x20000000));
247                                         wrmsr(MSR_K7_CLK_CTL, (l & 0x000fffff)|0x20000000, h);
248                                 }
249                         }
250                         break;
251         }
252
253         switch (c->x86) {
254         case 15:
255         /* Use K8 tuning for Fam10h and Fam11h */
256         case 0x10:
257         case 0x11:
258                 set_cpu_cap(c, X86_FEATURE_K8);
259                 break;
260         case 6:
261                 set_cpu_cap(c, X86_FEATURE_K7);
262                 break;
263         }
264         if (c->x86 >= 6)
265                 set_cpu_cap(c, X86_FEATURE_FXSAVE_LEAK);
266
267         display_cacheinfo(c);
268
269         if (cpuid_eax(0x80000000) >= 0x80000008)
270                 c->x86_max_cores = (cpuid_ecx(0x80000008) & 0xff) + 1;
271
272 #ifdef CONFIG_X86_HT
273         /*
274          * On a AMD multi core setup the lower bits of the APIC id
275          * distinguish the cores.
276          */
277         if (c->x86_max_cores > 1) {
278                 int cpu = smp_processor_id();
279                 unsigned bits = (cpuid_ecx(0x80000008) >> 12) & 0xf;
280
281                 if (bits == 0) {
282                         while ((1 << bits) < c->x86_max_cores)
283                                 bits++;
284                 }
285                 c->cpu_core_id = c->phys_proc_id & ((1<<bits)-1);
286                 c->phys_proc_id >>= bits;
287                 printk(KERN_INFO "CPU %d(%d) -> Core %d\n",
288                        cpu, c->x86_max_cores, c->cpu_core_id);
289         }
290 #endif
291
292         if (cpuid_eax(0x80000000) >= 0x80000006) {
293                 if ((c->x86 == 0x10) && (cpuid_edx(0x80000006) & 0xf000))
294                         num_cache_leaves = 4;
295                 else
296                         num_cache_leaves = 3;
297         }
298
299 #ifdef CONFIG_X86_LOCAL_APIC
300         if (amd_apic_timer_broken())
301                 local_apic_timer_disabled = 1;
302 #endif
303
304         /* K6s reports MCEs but don't actually have all the MSRs */
305         if (c->x86 < 6)
306                 clear_cpu_cap(c, X86_FEATURE_MCE);
307
308         if (cpu_has_xmm2)
309                 set_cpu_cap(c, X86_FEATURE_MFENCE_RDTSC);
310
311         if (c->x86 == 0x10)
312                 amd_enable_pci_ext_cfg(c);
313 }
314
315 static unsigned int __cpuinit amd_size_cache(struct cpuinfo_x86 *c, unsigned int size)
316 {
317         /* AMD errata T13 (order #21922) */
318         if ((c->x86 == 6)) {
319                 if (c->x86_model == 3 && c->x86_mask == 0)      /* Duron Rev A0 */
320                         size = 64;
321                 if (c->x86_model == 4 &&
322                     (c->x86_mask == 0 || c->x86_mask == 1))     /* Tbird rev A1/A2 */
323                         size = 256;
324         }
325         return size;
326 }
327
328 static struct cpu_dev amd_cpu_dev __cpuinitdata = {
329         .c_vendor       = "AMD",
330         .c_ident        = { "AuthenticAMD" },
331         .c_models = {
332                 { .vendor = X86_VENDOR_AMD, .family = 4, .model_names =
333                   {
334                           [3] = "486 DX/2",
335                           [7] = "486 DX/2-WB",
336                           [8] = "486 DX/4",
337                           [9] = "486 DX/4-WB",
338                           [14] = "Am5x86-WT",
339                           [15] = "Am5x86-WB"
340                   }
341                 },
342         },
343         .c_early_init   = early_init_amd,
344         .c_init         = init_amd,
345         .c_size_cache   = amd_size_cache,
346 };
347
348 cpu_vendor_dev_register(X86_VENDOR_AMD, &amd_cpu_dev);