1 files changed, 162 insertions, 19 deletions

diff --git a/arch/x86/kernel/cpu/mtrr/generic.c b/arch/x86/kernel/cpu/mtrr/generic.c
index 103d61a59b19..353efe4f5017 100644
--- a/arch/x86/kernel/cpu/mtrr/generic.c
+++ b/arch/x86/kernel/cpu/mtrr/generic.c
@@ -11,6 +11,7 @@
 #include <asm/cpufeature.h>
 #include <asm/processor-flags.h>
 #include <asm/tlbflush.h>
+#include <asm/pat.h>
 #include "mtrr.h"
 
 struct mtrr_state {
@@ -35,6 +36,8 @@ static struct fixed_range_block fixed_range_blocks[] = {
 
 static unsigned long smp_changes_mask;
 static struct mtrr_state mtrr_state = {};
+static int mtrr_state_set;
+static u64 tom2;
 
 #undef MODULE_PARAM_PREFIX
 #define MODULE_PARAM_PREFIX "mtrr."
@@ -42,6 +45,111 @@ static struct mtrr_state mtrr_state = {};
 static int mtrr_show;
 module_param_named(show, mtrr_show, bool, 0);
 
+/*
+ * Returns the effective MTRR type for the region
+ * Error returns:
+ * - 0xFE - when the range is "not entirely covered" by _any_ var range MTRR
+ * - 0xFF - when MTRR is not enabled
+ */
+u8 mtrr_type_lookup(u64 start, u64 end)
+{
+	int i;
+	u64 base, mask;
+	u8 prev_match, curr_match;
+
+	if (!mtrr_state_set)
+		return 0xFF;
+
+	if (!mtrr_state.enabled)
+		return 0xFF;
+
+	/* Make end inclusive end, instead of exclusive */
+	end--;
+
+	/* Look in fixed ranges. Just return the type as per start */
+	if (mtrr_state.have_fixed && (start < 0x100000)) {
+		int idx;
+
+		if (start < 0x80000) {
+			idx = 0;
+			idx += (start >> 16);
+			return mtrr_state.fixed_ranges[idx];
+		} else if (start < 0xC0000) {
+			idx = 1 * 8;
+			idx += ((start - 0x80000) >> 14);
+			return mtrr_state.fixed_ranges[idx];
+		} else if (start < 0x1000000) {
+			idx = 3 * 8;
+			idx += ((start - 0xC0000) >> 12);
+			return mtrr_state.fixed_ranges[idx];
+		}
+	}
+
+	/*
+	 * Look in variable ranges
+	 * Look of multiple ranges matching this address and pick type
+	 * as per MTRR precedence
+	 */
+	if (!mtrr_state.enabled & 2) {
+		return mtrr_state.def_type;
+	}
+
+	prev_match = 0xFF;
+	for (i = 0; i < num_var_ranges; ++i) {
+		unsigned short start_state, end_state;
+
+		if (!(mtrr_state.var_ranges[i].mask_lo & (1 << 11)))
+			continue;
+
+		base = (((u64)mtrr_state.var_ranges[i].base_hi) << 32) +
+		       (mtrr_state.var_ranges[i].base_lo & PAGE_MASK);
+		mask = (((u64)mtrr_state.var_ranges[i].mask_hi) << 32) +
+		       (mtrr_state.var_ranges[i].mask_lo & PAGE_MASK);
+
+		start_state = ((start & mask) == (base & mask));
+		end_state = ((end & mask) == (base & mask));
+		if (start_state != end_state)
+			return 0xFE;
+
+		if ((start & mask) != (base & mask)) {
+			continue;
+		}
+
+		curr_match = mtrr_state.var_ranges[i].base_lo & 0xff;
+		if (prev_match == 0xFF) {
+			prev_match = curr_match;
+			continue;
+		}
+
+		if (prev_match == MTRR_TYPE_UNCACHABLE ||
+		    curr_match == MTRR_TYPE_UNCACHABLE) {
+			return MTRR_TYPE_UNCACHABLE;
+		}
+
+		if ((prev_match == MTRR_TYPE_WRBACK &&
+		     curr_match == MTRR_TYPE_WRTHROUGH) ||
+		    (prev_match == MTRR_TYPE_WRTHROUGH &&
+		     curr_match == MTRR_TYPE_WRBACK)) {
+			prev_match = MTRR_TYPE_WRTHROUGH;
+			curr_match = MTRR_TYPE_WRTHROUGH;
+		}
+
+		if (prev_match != curr_match) {
+			return MTRR_TYPE_UNCACHABLE;
+		}
+	}
+
+	if (tom2) {
+		if (start >= (1ULL<<32) && (end < tom2))
+			return MTRR_TYPE_WRBACK;
+	}
+
+	if (prev_match != 0xFF)
+		return prev_match;
+
+	return mtrr_state.def_type;
+}
+
 /*  Get the MSR pair relating to a var range  */
 static void
 get_mtrr_var_range(unsigned int index, struct mtrr_var_range *vr)
@@ -79,12 +187,16 @@ static void print_fixed(unsigned base, unsigned step, const mtrr_type*types)
 			base, base + step - 1, mtrr_attrib_to_str(*types));
 }
 
+static void prepare_set(void);
+static void post_set(void);
+
 /*  Grab all of the MTRR state for this CPU into *state  */
 void __init get_mtrr_state(void)
 {
 	unsigned int i;
 	struct mtrr_var_range *vrs;
 	unsigned lo, dummy;
+	unsigned long flags;
 
 	vrs = mtrr_state.var_ranges;
 
@@ -100,6 +212,15 @@ void __init get_mtrr_state(void)
 	mtrr_state.def_type = (lo & 0xff);
 	mtrr_state.enabled = (lo & 0xc00) >> 10;
 
+	if (amd_special_default_mtrr()) {
+		unsigned lo, hi;
+		/* TOP_MEM2 */
+		rdmsr(MSR_K8_TOP_MEM2, lo, hi);
+		tom2 = hi;
+		tom2 <<= 32;
+		tom2 |= lo;
+		tom2 &= 0xffffff8000000ULL;
+	}
 	if (mtrr_show) {
 		int high_width;
 
@@ -130,7 +251,22 @@ void __init get_mtrr_state(void)
 			else
 				printk(KERN_INFO "MTRR %u disabled\n", i);
 		}
+		if (tom2) {
+			printk(KERN_INFO "TOM2: %016llx aka %lldM\n",
+					  tom2, tom2>>20);
+		}
 	}
+	mtrr_state_set = 1;
+
+	/* PAT setup for BP. We need to go through sync steps here */
+	local_irq_save(flags);
+	prepare_set();
+
+	pat_init();
+
+	post_set();
+	local_irq_restore(flags);
+
 }
 
 /*  Some BIOS's are fucked and don't set all MTRRs the same!  */
@@ -176,12 +312,13 @@ static inline void k8_enable_fixed_iorrs(void)
 }
 
 /**
- * Checks and updates an fixed-range MTRR if it differs from the value it
- * should have. If K8 extentions are wanted, update the K8 SYSCFG MSR also.
- * see AMD publication no. 24593, chapter 7.8.1, page 233 for more information
- * \param msr MSR address of the MTTR which should be checked and updated
- * \param changed pointer which indicates whether the MTRR needed to be changed
- * \param msrwords pointer to the MSR values which the MSR should have
+ * set_fixed_range - checks & updates a fixed-range MTRR if it differs from the value it should have
+ * @msr: MSR address of the MTTR which should be checked and updated
+ * @changed: pointer which indicates whether the MTRR needed to be changed
+ * @msrwords: pointer to the MSR values which the MSR should have
+ *
+ * If K8 extentions are wanted, update the K8 SYSCFG MSR also.
+ * See AMD publication no. 24593, chapter 7.8.1, page 233 for more information.
  */
 static void set_fixed_range(int msr, bool *changed, unsigned int *msrwords)
 {
@@ -199,12 +336,15 @@ static void set_fixed_range(int msr, bool *changed, unsigned int *msrwords)
 	}
 }
 
+/**
+ * generic_get_free_region - Get a free MTRR.
+ * @base: The starting (base) address of the region.
+ * @size: The size (in bytes) of the region.
+ * @replace_reg: mtrr index to be replaced; set to invalid value if none.
+ *
+ * Returns: The index of the region on success, else negative on error.
+ */
 int generic_get_free_region(unsigned long base, unsigned long size, int replace_reg)
-/*  [SUMMARY] Get a free MTRR.
-    <base> The starting (base) address of the region.
-    <size> The size (in bytes) of the region.
-    [RETURNS] The index of the region on success, else -1 on error.
-*/
 {
 	int i, max;
 	mtrr_type ltype;
@@ -249,8 +389,8 @@ static void generic_get_mtrr(unsigned int reg, unsigned long *base,
 }
 
 /**
- * Checks and updates the fixed-range MTRRs if they differ from the saved set
- * \param frs pointer to fixed-range MTRR values, saved by get_fixed_ranges()
+ * set_fixed_ranges - checks & updates the fixed-range MTRRs if they differ from the saved set
+ * @frs: pointer to fixed-range MTRR values, saved by get_fixed_ranges()
  */
 static int set_fixed_ranges(mtrr_type * frs)
 {
@@ -294,13 +434,13 @@ static bool set_mtrr_var_ranges(unsigned int index, struct mtrr_var_range *vr)
 
 static u32 deftype_lo, deftype_hi;
 
+/**
+ * set_mtrr_state - Set the MTRR state for this CPU.
+ *
+ * NOTE: The CPU must already be in a safe state for MTRR changes.
+ * RETURNS: 0 if no changes made, else a mask indicating what was changed.
+ */
 static unsigned long set_mtrr_state(void)
-/*  [SUMMARY] Set the MTRR state for this CPU.
-    <state> The MTRR state information to read.
-    <ctxt> Some relevant CPU context.
-    [NOTE] The CPU must already be in a safe state for MTRR changes.
-    [RETURNS] 0 if no changes made, else a mask indication what was changed.
-*/
 {
 	unsigned int i;
 	unsigned long change_mask = 0;
@@ -393,6 +533,9 @@ static void generic_set_all(void)
 	/* Actually set the state */
 	mask = set_mtrr_state();
 
+	/* also set PAT */
+	pat_init();
+
 	post_set();
 	local_irq_restore(flags);