x86: Add support for more than 8 MTRRs

At present the mtrr command only support 8 MTRRs. Some SoCs have more than
that. Update the implementation to support up to 10. Read the number of
MTRRs dynamically instead.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

diff --git a/arch/x86/cpu/mtrr.c b/arch/x86/cpu/mtrr.c
index 08fa80f8bc7b27714b90f85c32d1edb74f45bdf5..5180eb06fcd4117dae91d80b9c0df094ea9e017c 100644 (file)
--- a/arch/x86/cpu/mtrr.c
+++ b/arch/x86/cpu/mtrr.c
@@ -67,9 +67,10 @@ static void set_var_mtrr(uint reg, uint type, uint64_t start, uint64_t size)
 
 void mtrr_read_all(struct mtrr_info *info)
 {
+       int reg_count = mtrr_get_var_count();
        int i;
 
-       for (i = 0; i < MTRR_COUNT; i++) {
+       for (i = 0; i < reg_count; i++) {
                info->mtrr[i].base = native_read_msr(MTRR_PHYS_BASE_MSR(i));
                info->mtrr[i].mask = native_read_msr(MTRR_PHYS_MASK_MSR(i));
        }
@@ -77,10 +78,11 @@ void mtrr_read_all(struct mtrr_info *info)
 
 void mtrr_write_all(struct mtrr_info *info)
 {
+       int reg_count = mtrr_get_var_count();
        struct mtrr_state state;
        int i;
 
-       for (i = 0; i < MTRR_COUNT; i++) {
+       for (i = 0; i < reg_count; i++) {
                mtrr_open(&state, true);
                wrmsrl(MTRR_PHYS_BASE_MSR(i), info->mtrr[i].base);
                wrmsrl(MTRR_PHYS_MASK_MSR(i), info->mtrr[i].mask);
@@ -156,7 +158,7 @@ int mtrr_commit(bool do_caches)
 
        /* Clear the ones that are unused */
        debug("clear\n");
-       for (; i < MTRR_COUNT; i++)
+       for (; i < MTRR_MAX_COUNT; i++)
                wrmsrl(MTRR_PHYS_MASK_MSR(i), 0);
        debug("close\n");
        mtrr_close(&state, do_caches);
@@ -196,7 +198,7 @@ int mtrr_add_request(int type, uint64_t start, uint64_t size)
        return 0;
 }
 
-static int get_var_mtrr_count(void)
+int mtrr_get_var_count(void)
 {
        return msr_read(MSR_MTRR_CAP_MSR).lo & MSR_MTRR_CAP_VCNT;
 }
@@ -207,7 +209,7 @@ static int get_free_var_mtrr(void)
        int vcnt;
        int i;
 
-       vcnt = get_var_mtrr_count();
+       vcnt = mtrr_get_var_count();
 
        /* Identify the first var mtrr which is not valid */
        for (i = 0; i < vcnt; i++) {

diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h
index 48db1dd82f73d27ee15ef63944bbe436735e4198..3a98aacdef546cd58147ea79ce73b5cf1ce030c8 100644 (file)
--- a/arch/x86/include/asm/mtrr.h
+++ b/arch/x86/include/asm/mtrr.h
@@ -36,8 +36,8 @@
 
 #define MTRR_BASE_TYPE_MASK    0x7
 
-/* Number of MTRRs supported */
-#define MTRR_COUNT             8
+/* Maximum number of MTRRs supported - see also mtrr_get_var_count() */
+#define MTRR_MAX_COUNT         10
 
 #define NUM_FIXED_MTRRS                11
 #define RANGES_PER_FIXED_MTRR  8
@@ -87,7 +87,7 @@ struct mtrr {
  * @mtrr: Information about each mtrr
  */
 struct mtrr_info {
-       struct mtrr mtrr[MTRR_COUNT];
+       struct mtrr mtrr[MTRR_MAX_COUNT];
 };
 
 /**
@@ -180,6 +180,15 @@ int mtrr_set_valid(int cpu_select, int reg, bool valid);
  */
 int mtrr_set(int cpu_select, int reg, u64 base, u64 mask);
 
+/**
+ * mtrr_get_var_count() - Get the number of variable MTRRs
+ *
+ * Some CPUs have more than 8 MTRRs. This function returns the actual number
+ *
+ * @return number of variable MTRRs
+ */
+int mtrr_get_var_count(void);
+
 #endif
 
 #if ((CONFIG_XIP_ROM_SIZE & (CONFIG_XIP_ROM_SIZE - 1)) != 0)

diff --git a/cmd/x86/mtrr.c b/cmd/x86/mtrr.c
index 99efecb9d8e5ed021373eb82541e5316b250426f..fc61a549b029e5641283e1d3bf743c17e45ea72f 100644 (file)
--- a/cmd/x86/mtrr.c
+++ b/cmd/x86/mtrr.c
@@ -27,7 +27,7 @@ static void read_mtrrs(void *arg)
        mtrr_read_all(info);
 }
 
-static int do_mtrr_list(int cpu_select)
+static int do_mtrr_list(int reg_count, int cpu_select)
 {
        struct mtrr_info info;
        int ret;
@@ -39,7 +39,7 @@ static int do_mtrr_list(int cpu_select)
        ret = mp_run_on_cpus(cpu_select, read_mtrrs, &info);
        if (ret)
                return log_msg_ret("run", ret);
-       for (i = 0; i < MTRR_COUNT; i++) {
+       for (i = 0; i < reg_count; i++) {
                const char *type = "Invalid";
                uint64_t base, mask, size;
                bool valid;
@@ -98,6 +98,7 @@ static int do_mtrr_set(int cpu_select, uint reg, int argc, char *const argv[])
 static int do_mtrr(struct cmd_tbl *cmdtp, int flag, int argc,
                   char *const argv[])
 {
+       int reg_count = mtrr_get_var_count();
        int cmd;
        int cpu_select;
        uint reg;
@@ -126,7 +127,7 @@ static int do_mtrr(struct cmd_tbl *cmdtp, int flag, int argc,
                if (argc < 2)
                        return CMD_RET_USAGE;
                reg = simple_strtoul(argv[1], NULL, 16);
-               if (reg >= MTRR_COUNT) {
+               if (reg >= reg_count) {
                        printf("Invalid register number\n");
                        return CMD_RET_USAGE;
                }
@@ -145,7 +146,7 @@ static int do_mtrr(struct cmd_tbl *cmdtp, int flag, int argc,
                        if (!first)
                                printf("\n");
                        printf("CPU %d:\n", i);
-                       ret = do_mtrr_list(i);
+                       ret = do_mtrr_list(reg_count, i);
                        if (ret) {
                                printf("Failed to read CPU %d (err=%d)\n", i,
                                       ret);