[PATCH 6/9] x86: make amd_64 have 32 bit code
From: Yinghai Lu
Date: Sun Sep 07 2008 - 21:00:51 EST
Signed-off-by: Yinghai Lu <yhlu.kernel@xxxxxxxxx>
---
arch/x86/kernel/cpu/amd_64.c | 259 ++++++++++++++++++++++++++++++++++++++++--
1 files changed, 247 insertions(+), 12 deletions(-)
diff --git a/arch/x86/kernel/cpu/amd_64.c b/arch/x86/kernel/cpu/amd_64.c
index 1d83601..32e7352 100644
--- a/arch/x86/kernel/cpu/amd_64.c
+++ b/arch/x86/kernel/cpu/amd_64.c
@@ -16,7 +16,171 @@
#include "cpu.h"
-#ifdef CONFIG_NUMA
+#ifdef CONFIG_X86_32
+/*
+ * B step AMD K6 before B 9730xxxx have hardware bugs that can cause
+ * misexecution of code under Linux. Owners of such processors should
+ * contact AMD for precise details and a CPU swap.
+ *
+ * See http://www.multimania.com/poulot/k6bug.html
+ * http://www.amd.com/K6/k6docs/revgd.html
+ *
+ * The following test is erm.. interesting. AMD neglected to up
+ * the chip setting when fixing the bug but they also tweaked some
+ * performance at the same time..
+ */
+
+extern void vide(void);
+__asm__(".align 4\nvide: ret");
+
+static void __cpuinit init_amd_k5(struct cpuinfo_x86 *c)
+{
+/*
+ * General Systems BIOSen alias the cpu frequency registers
+ * of the Elan at 0x000df000. Unfortuantly, one of the Linux
+ * drivers subsequently pokes it, and changes the CPU speed.
+ * Workaround : Remove the unneeded alias.
+ */
+#define CBAR (0xfffc) /* Configuration Base Address (32-bit) */
+#define CBAR_ENB (0x80000000)
+#define CBAR_KEY (0X000000CB)
+ if (c->x86_model == 9 || c->x86_model == 10) {
+ if (inl (CBAR) & CBAR_ENB)
+ outl (0 | CBAR_KEY, CBAR);
+ }
+}
+
+
+static void __cpuinit init_amd_k6(struct cpuinfo_x86 *c)
+{
+ u32 l, h;
+ int mbytes = num_physpages >> (20-PAGE_SHIFT);
+
+ if (c->x86_model < 6) {
+ /* Based on AMD doc 20734R - June 2000 */
+ if (c->x86_model == 0) {
+ clear_cpu_cap(c, X86_FEATURE_APIC);
+ set_cpu_cap(c, X86_FEATURE_PGE);
+ }
+ return;
+ }
+
+ if (c->x86_model == 6 && c->x86_mask == 1) {
+ const int K6_BUG_LOOP = 1000000;
+ int n;
+ void (*f_vide)(void);
+ unsigned long d, d2;
+
+ printk(KERN_INFO "AMD K6 stepping B detected - ");
+
+ /*
+ * It looks like AMD fixed the 2.6.2 bug and improved indirect
+ * calls at the same time.
+ */
+
+ n = K6_BUG_LOOP;
+ f_vide = vide;
+ rdtscl(d);
+ while (n--)
+ f_vide();
+ rdtscl(d2);
+ d = d2-d;
+
+ if (d > 20*K6_BUG_LOOP)
+ printk("system stability may be impaired when more than 32 MB are used.\n");
+ else
+ printk("probably OK (after B9730xxxx).\n");
+ printk(KERN_INFO "Please see http://membres.lycos.fr/poulot/k6bug.html\n";);
+ }
+
+ /* K6 with old style WHCR */
+ if (c->x86_model < 8 ||
+ (c->x86_model == 8 && c->x86_mask < 8)) {
+ /* We can only write allocate on the low 508Mb */
+ if (mbytes > 508)
+ mbytes = 508;
+
+ rdmsr(MSR_K6_WHCR, l, h);
+ if ((l&0x0000FFFF) == 0) {
+ unsigned long flags;
+ l = (1<<0)|((mbytes/4)<<1);
+ local_irq_save(flags);
+ wbinvd();
+ wrmsr(MSR_K6_WHCR, l, h);
+ local_irq_restore(flags);
+ printk(KERN_INFO "Enabling old style K6 write allocation for %d Mb\n",
+ mbytes);
+ }
+ return;
+ }
+
+ if ((c->x86_model == 8 && c->x86_mask > 7) ||
+ c->x86_model == 9 || c->x86_model == 13) {
+ /* The more serious chips .. */
+
+ if (mbytes > 4092)
+ mbytes = 4092;
+
+ rdmsr(MSR_K6_WHCR, l, h);
+ if ((l&0xFFFF0000) == 0) {
+ unsigned long flags;
+ l = ((mbytes>>2)<<22)|(1<<16);
+ local_irq_save(flags);
+ wbinvd();
+ wrmsr(MSR_K6_WHCR, l, h);
+ local_irq_restore(flags);
+ printk(KERN_INFO "Enabling new style K6 write allocation for %d Mb\n",
+ mbytes);
+ }
+
+ return;
+ }
+
+ if (c->x86_model == 10) {
+ /* AMD Geode LX is model 10 */
+ /* placeholder for any needed mods */
+ return;
+ }
+}
+
+static void __cpuinit init_amd_k7(struct cpuinfo_x86 *c)
+{
+ u32 l, h;
+
+ /*
+ * Bit 15 of Athlon specific MSR 15, needs to be 0
+ * to enable SSE on Palomino/Morgan/Barton CPU's.
+ * If the BIOS didn't enable it already, enable it here.
+ */
+ if (c->x86_model >= 6 && c->x86_model <= 10) {
+ if (!cpu_has(c, X86_FEATURE_XMM)) {
+ printk(KERN_INFO "Enabling disabled K7/SSE Support.\n");
+ rdmsr(MSR_K7_HWCR, l, h);
+ l &= ~0x00008000;
+ wrmsr(MSR_K7_HWCR, l, h);
+ set_cpu_cap(c, X86_FEATURE_XMM);
+ }
+ }
+
+ /*
+ * It's been determined by AMD that Athlons since model 8 stepping 1
+ * are more robust with CLK_CTL set to 200xxxxx instead of 600xxxxx
+ * As per AMD technical note 27212 0.2
+ */
+ if ((c->x86_model == 8 && c->x86_mask >= 1) || (c->x86_model > 8)) {
+ rdmsr(MSR_K7_CLK_CTL, l, h);
+ if ((l & 0xfff00000) != 0x20000000) {
+ printk ("CPU: CLK_CTL MSR was %x. Reprogramming to %x\n", l,
+ ((l & 0x000fffff)|0x20000000));
+ wrmsr(MSR_K7_CLK_CTL, (l & 0x000fffff)|0x20000000, h);
+ }
+ }
+
+ set_cpu_cap(c, X86_FEATURE_K7);
+}
+#endif
+
+#if defined(CONFIG_NUMA) && defined(CONFIG_X86_64)
static int __cpuinit nearby_node(int apicid)
{
int i, node;
@@ -41,7 +205,7 @@ static int __cpuinit nearby_node(int apicid)
*/
static void __cpuinit amd_detect_cmp(struct cpuinfo_x86 *c)
{
-#ifdef CONFIG_SMP
+#ifdef CONFIG_X86_HT
unsigned bits;
bits = c->x86_coreid_bits;
@@ -55,7 +219,7 @@ static void __cpuinit amd_detect_cmp(struct cpuinfo_x86 *c)
static void __cpuinit srat_detect_node(struct cpuinfo_x86 *c)
{
-#ifdef CONFIG_NUMA
+#if defined(CONFIG_NUMA) && defined(CONFIG_X86_64)
int cpu = smp_processor_id();
int node;
unsigned apicid = hard_smp_processor_id();
@@ -91,7 +255,7 @@ static void __cpuinit srat_detect_node(struct cpuinfo_x86 *c)
static void __cpuinit early_init_amd_mc(struct cpuinfo_x86 *c)
{
-#ifdef CONFIG_SMP
+#ifdef CONFIG_X86_HT
unsigned bits, ecx;
/* Multi core CPU? */
@@ -112,7 +276,6 @@ static void __cpuinit early_init_amd_mc(struct cpuinfo_x86 *c)
}
c->x86_coreid_bits = bits;
-
#endif
}
@@ -124,15 +287,21 @@ static void __cpuinit early_init_amd(struct cpuinfo_x86 *c)
if (c->x86_power & (1<<8))
set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
+#ifdef CONFIG_X86_64
set_cpu_cap(c, X86_FEATURE_SYSCALL32);
+#else
+ /* Set MTRR capability flag if appropriate */
+ if (c->x86 == 5)
+ if (c->x86_model == 13 || c->x86_model == 9 ||
+ (c->x86_model == 8 && c->x86_mask >= 8))
+ set_cpu_cap(c, X86_FEATURE_K6_MTRR);
+#endif
}
static void __cpuinit init_amd(struct cpuinfo_x86 *c)
{
- unsigned level;
-
#ifdef CONFIG_SMP
- unsigned long value;
+ unsigned long long value;
/*
* Disable TLB flush filter by setting HWCR.FFDIS on K8
@@ -142,26 +311,55 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
* Errata 122 for all steppings (F+ have it disabled by default)
*/
if (c->x86 == 0xf) {
- rdmsrl(MSR_K8_HWCR, value);
+ rdmsrl(MSR_K7_HWCR, value);
value |= 1 << 6;
- wrmsrl(MSR_K8_HWCR, value);
+ wrmsrl(MSR_K7_HWCR, value);
}
#endif
early_init_amd(c);
- /* Bit 31 in normal CPUID used for nonstandard 3DNow ID;
- 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway */
+ /*
+ * Bit 31 in normal CPUID used for nonstandard 3DNow ID;
+ * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
+ */
clear_cpu_cap(c, 0*32+31);
+#ifdef CONFIG_X86_64
/* On C+ stepping K8 rep microcode works well for copy/memset */
if (c->x86 == 0xf) {
+ u32 level;
+
level = cpuid_eax(1);
if((level >= 0x0f48 && level < 0x0f50) || level >= 0x0f58)
set_cpu_cap(c, X86_FEATURE_REP_GOOD);
}
if (c->x86 == 0x10 || c->x86 == 0x11)
set_cpu_cap(c, X86_FEATURE_REP_GOOD);
+#else
+
+ /*
+ * FIXME: We should handle the K5 here. Set up the write
+ * range and also turn on MSR 83 bits 4 and 31 (write alloc,
+ * no bus pipeline)
+ */
+
+ switch (c->x86) {
+ case 4:
+ init_amd_k5(c);
+ break;
+ case 5:
+ init_amd_k6(c);
+ break;
+ case 6: /* An Athlon/Duron */
+ init_amd_k7(c);
+ break;
+ }
+
+ /* K6s reports MCEs but don't actually have all the MSRs */
+ if (c->x86 < 6)
+ clear_cpu_cap(c, X86_FEATURE_MCE);
+#endif
/* Enable workaround for FXSAVE leak */
if (c->x86 >= 6)
@@ -176,6 +374,7 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
break;
}
}
+
display_cacheinfo(c);
/* Multi core CPU? */
@@ -184,6 +383,10 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
srat_detect_node(c);
}
+#ifdef CONFIG_X86_32
+ detect_ht(c);
+#endif
+
if (c->extended_cpuid_level >= 0x80000006) {
if ((c->x86 >= 0x0f) && (cpuid_edx(0x80000006) & 0xf000))
num_cache_leaves = 4;
@@ -199,6 +402,7 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
set_cpu_cap(c, X86_FEATURE_MFENCE_RDTSC);
}
+#ifdef CONFIG_X86_64
if (c->x86 == 0x10) {
/* do this for boot cpu */
if (c == &boot_cpu_data)
@@ -225,11 +429,42 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
set_memory_4k((unsigned long)__va(tseg), 1);
}
}
+#endif
+}
+
+#ifdef CONFIG_X86_32
+static unsigned int __cpuinit amd_size_cache(struct cpuinfo_x86 *c, unsigned int size)
+{
+ /* AMD errata T13 (order #21922) */
+ if ((c->x86 == 6)) {
+ if (c->x86_model == 3 && c->x86_mask == 0) /* Duron Rev A0 */
+ size = 64;
+ if (c->x86_model == 4 &&
+ (c->x86_mask == 0 || c->x86_mask == 1)) /* Tbird rev A1/A2 */
+ size = 256;
+ }
+ return size;
}
+#endif
static struct cpu_dev amd_cpu_dev __cpuinitdata = {
.c_vendor = "AMD",
.c_ident = { "AuthenticAMD" },
+#ifdef CONFIG_X86_32
+ .c_models = {
+ { .vendor = X86_VENDOR_AMD, .family = 4, .model_names =
+ {
+ [3] = "486 DX/2",
+ [7] = "486 DX/2-WB",
+ [8] = "486 DX/4",
+ [9] = "486 DX/4-WB",
+ [14] = "Am5x86-WT",
+ [15] = "Am5x86-WB"
+ }
+ },
+ },
+ .c_size_cache = amd_size_cache,
+#endif
.c_early_init = early_init_amd,
.c_init = init_amd,
.c_x86_vendor = X86_VENDOR_AMD,
--
1.5.4.5
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