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-rw-r--r--arch/x86/kernel/cpu/mtrr/cyrix.c2
-rw-r--r--arch/x86/kernel/cpu/mtrr/generic.c23
-rw-r--r--arch/x86/kernel/cpu/mtrr/main.c87
3 files changed, 93 insertions, 19 deletions
diff --git a/arch/x86/kernel/cpu/mtrr/cyrix.c b/arch/x86/kernel/cpu/mtrr/cyrix.c
index 68a3343e5798..9e451b0876b5 100644
--- a/arch/x86/kernel/cpu/mtrr/cyrix.c
+++ b/arch/x86/kernel/cpu/mtrr/cyrix.c
@@ -167,7 +167,7 @@ static void post_set(void)
setCx86(CX86_CCR3, ccr3);
/* Enable caches */
- write_cr0(read_cr0() & 0xbfffffff);
+ write_cr0(read_cr0() & ~X86_CR0_CD);
/* Restore value of CR4 */
if (cpu_has_pge)
diff --git a/arch/x86/kernel/cpu/mtrr/generic.c b/arch/x86/kernel/cpu/mtrr/generic.c
index fa72a39e5d46..d4cdfa67509e 100644
--- a/arch/x86/kernel/cpu/mtrr/generic.c
+++ b/arch/x86/kernel/cpu/mtrr/generic.c
@@ -510,8 +510,9 @@ generic_get_free_region(unsigned long base, unsigned long size, int replace_reg)
static void generic_get_mtrr(unsigned int reg, unsigned long *base,
unsigned long *size, mtrr_type *type)
{
- unsigned int mask_lo, mask_hi, base_lo, base_hi;
- unsigned int tmp, hi;
+ u32 mask_lo, mask_hi, base_lo, base_hi;
+ unsigned int hi;
+ u64 tmp, mask;
/*
* get_mtrr doesn't need to update mtrr_state, also it could be called
@@ -532,18 +533,18 @@ static void generic_get_mtrr(unsigned int reg, unsigned long *base,
rdmsr(MTRRphysBase_MSR(reg), base_lo, base_hi);
/* Work out the shifted address mask: */
- tmp = mask_hi << (32 - PAGE_SHIFT) | mask_lo >> PAGE_SHIFT;
- mask_lo = size_or_mask | tmp;
+ tmp = (u64)mask_hi << (32 - PAGE_SHIFT) | mask_lo >> PAGE_SHIFT;
+ mask = size_or_mask | tmp;
/* Expand tmp with high bits to all 1s: */
- hi = fls(tmp);
+ hi = fls64(tmp);
if (hi > 0) {
- tmp |= ~((1<<(hi - 1)) - 1);
+ tmp |= ~((1ULL<<(hi - 1)) - 1);
- if (tmp != mask_lo) {
+ if (tmp != mask) {
printk(KERN_WARNING "mtrr: your BIOS has configured an incorrect mask, fixing it.\n");
add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
- mask_lo = tmp;
+ mask = tmp;
}
}
@@ -551,8 +552,8 @@ static void generic_get_mtrr(unsigned int reg, unsigned long *base,
* This works correctly if size is a power of two, i.e. a
* contiguous range:
*/
- *size = -mask_lo;
- *base = base_hi << (32 - PAGE_SHIFT) | base_lo >> PAGE_SHIFT;
+ *size = -mask;
+ *base = (u64)base_hi << (32 - PAGE_SHIFT) | base_lo >> PAGE_SHIFT;
*type = base_lo & 0xff;
out_put_cpu:
@@ -701,7 +702,7 @@ static void post_set(void) __releases(set_atomicity_lock)
mtrr_wrmsr(MSR_MTRRdefType, deftype_lo, deftype_hi);
/* Enable caches */
- write_cr0(read_cr0() & 0xbfffffff);
+ write_cr0(read_cr0() & ~X86_CR0_CD);
/* Restore value of CR4 */
if (cpu_has_pge)
diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c
index 726bf963c227..f961de9964c7 100644
--- a/arch/x86/kernel/cpu/mtrr/main.c
+++ b/arch/x86/kernel/cpu/mtrr/main.c
@@ -51,9 +51,13 @@
#include <asm/e820.h>
#include <asm/mtrr.h>
#include <asm/msr.h>
+#include <asm/pat.h>
#include "mtrr.h"
+/* arch_phys_wc_add returns an MTRR register index plus this offset. */
+#define MTRR_TO_PHYS_WC_OFFSET 1000
+
u32 num_var_ranges;
unsigned int mtrr_usage_table[MTRR_MAX_VAR_RANGES];
@@ -305,7 +309,8 @@ int mtrr_add_page(unsigned long base, unsigned long size,
return -EINVAL;
}
- if (base & size_or_mask || size & size_or_mask) {
+ if ((base | (base + size - 1)) >>
+ (boot_cpu_data.x86_phys_bits - PAGE_SHIFT)) {
pr_warning("mtrr: base or size exceeds the MTRR width\n");
return -EINVAL;
}
@@ -524,6 +529,73 @@ int mtrr_del(int reg, unsigned long base, unsigned long size)
}
EXPORT_SYMBOL(mtrr_del);
+/**
+ * arch_phys_wc_add - add a WC MTRR and handle errors if PAT is unavailable
+ * @base: Physical base address
+ * @size: Size of region
+ *
+ * If PAT is available, this does nothing. If PAT is unavailable, it
+ * attempts to add a WC MTRR covering size bytes starting at base and
+ * logs an error if this fails.
+ *
+ * Drivers must store the return value to pass to mtrr_del_wc_if_needed,
+ * but drivers should not try to interpret that return value.
+ */
+int arch_phys_wc_add(unsigned long base, unsigned long size)
+{
+ int ret;
+
+ if (pat_enabled)
+ return 0; /* Success! (We don't need to do anything.) */
+
+ ret = mtrr_add(base, size, MTRR_TYPE_WRCOMB, true);
+ if (ret < 0) {
+ pr_warn("Failed to add WC MTRR for [%p-%p]; performance may suffer.",
+ (void *)base, (void *)(base + size - 1));
+ return ret;
+ }
+ return ret + MTRR_TO_PHYS_WC_OFFSET;
+}
+EXPORT_SYMBOL(arch_phys_wc_add);
+
+/*
+ * arch_phys_wc_del - undoes arch_phys_wc_add
+ * @handle: Return value from arch_phys_wc_add
+ *
+ * This cleans up after mtrr_add_wc_if_needed.
+ *
+ * The API guarantees that mtrr_del_wc_if_needed(error code) and
+ * mtrr_del_wc_if_needed(0) do nothing.
+ */
+void arch_phys_wc_del(int handle)
+{
+ if (handle >= 1) {
+ WARN_ON(handle < MTRR_TO_PHYS_WC_OFFSET);
+ mtrr_del(handle - MTRR_TO_PHYS_WC_OFFSET, 0, 0);
+ }
+}
+EXPORT_SYMBOL(arch_phys_wc_del);
+
+/*
+ * phys_wc_to_mtrr_index - translates arch_phys_wc_add's return value
+ * @handle: Return value from arch_phys_wc_add
+ *
+ * This will turn the return value from arch_phys_wc_add into an mtrr
+ * index suitable for debugging.
+ *
+ * Note: There is no legitimate use for this function, except possibly
+ * in printk line. Alas there is an illegitimate use in some ancient
+ * drm ioctls.
+ */
+int phys_wc_to_mtrr_index(int handle)
+{
+ if (handle < MTRR_TO_PHYS_WC_OFFSET)
+ return -1;
+ else
+ return handle - MTRR_TO_PHYS_WC_OFFSET;
+}
+EXPORT_SYMBOL_GPL(phys_wc_to_mtrr_index);
+
/*
* HACK ALERT!
* These should be called implicitly, but we can't yet until all the initcall
@@ -583,6 +655,7 @@ static struct syscore_ops mtrr_syscore_ops = {
int __initdata changed_by_mtrr_cleanup;
+#define SIZE_OR_MASK_BITS(n) (~((1ULL << ((n) - PAGE_SHIFT)) - 1))
/**
* mtrr_bp_init - initialize mtrrs on the boot CPU
*
@@ -600,7 +673,7 @@ void __init mtrr_bp_init(void)
if (cpu_has_mtrr) {
mtrr_if = &generic_mtrr_ops;
- size_or_mask = 0xff000000; /* 36 bits */
+ size_or_mask = SIZE_OR_MASK_BITS(36);
size_and_mask = 0x00f00000;
phys_addr = 36;
@@ -619,7 +692,7 @@ void __init mtrr_bp_init(void)
boot_cpu_data.x86_mask == 0x4))
phys_addr = 36;
- size_or_mask = ~((1ULL << (phys_addr - PAGE_SHIFT)) - 1);
+ size_or_mask = SIZE_OR_MASK_BITS(phys_addr);
size_and_mask = ~size_or_mask & 0xfffff00000ULL;
} else if (boot_cpu_data.x86_vendor == X86_VENDOR_CENTAUR &&
boot_cpu_data.x86 == 6) {
@@ -627,7 +700,7 @@ void __init mtrr_bp_init(void)
* VIA C* family have Intel style MTRRs,
* but don't support PAE
*/
- size_or_mask = 0xfff00000; /* 32 bits */
+ size_or_mask = SIZE_OR_MASK_BITS(32);
size_and_mask = 0;
phys_addr = 32;
}
@@ -637,21 +710,21 @@ void __init mtrr_bp_init(void)
if (cpu_has_k6_mtrr) {
/* Pre-Athlon (K6) AMD CPU MTRRs */
mtrr_if = mtrr_ops[X86_VENDOR_AMD];
- size_or_mask = 0xfff00000; /* 32 bits */
+ size_or_mask = SIZE_OR_MASK_BITS(32);
size_and_mask = 0;
}
break;
case X86_VENDOR_CENTAUR:
if (cpu_has_centaur_mcr) {
mtrr_if = mtrr_ops[X86_VENDOR_CENTAUR];
- size_or_mask = 0xfff00000; /* 32 bits */
+ size_or_mask = SIZE_OR_MASK_BITS(32);
size_and_mask = 0;
}
break;
case X86_VENDOR_CYRIX:
if (cpu_has_cyrix_arr) {
mtrr_if = mtrr_ops[X86_VENDOR_CYRIX];
- size_or_mask = 0xfff00000; /* 32 bits */
+ size_or_mask = SIZE_OR_MASK_BITS(32);
size_and_mask = 0;
}
break;
generated by cgit v1.2.3 (git 2.0.4) at 2025-08-05 11:07:06 +0000