On Mon, Oct 7, 2019 at 9:53 PM Bin Meng bmeng.cn@gmail.com wrote:
On Wed, Sep 25, 2019 at 10:58 PM Simon Glass sjg@chromium.org wrote:
Normally U-Boot handles MTRRs through an add/commit process which overwrites all MTRRs. But in very early boot it is not desirable to clear the existing MTRRs since they may be in use and it can cause a hang.
Add a new mtrr_set_next_var() function which sets up the next available MTRR to the required region.
Signed-off-by: Simon Glass sjg@chromium.org
arch/x86/cpu/mtrr.c | 38 +++++++++++++++++++++++++++++++++++++ arch/x86/include/asm/mtrr.h | 12 ++++++++++++ 2 files changed, 50 insertions(+)
diff --git a/arch/x86/cpu/mtrr.c b/arch/x86/cpu/mtrr.c index 6218d149e30..1a7c292fa8b 100644 --- a/arch/x86/cpu/mtrr.c +++ b/arch/x86/cpu/mtrr.c @@ -112,3 +112,41 @@ int mtrr_add_request(int type, uint64_t start, uint64_t size)
return 0;}
+static int get_var_mtrr_count(void) +{
return msr_read(MSR_MTRR_CAP_MSR).lo & MSR_MTRR_CAP_VCNT;+}
+static int get_free_var_mtrr(void) +{
struct msr_t maskm;int vcnt;int i;vcnt = get_var_mtrr_count();/* Identify the first var mtrr which is not valid */for (i = 0; i < vcnt; i++) {maskm = msr_read(MTRR_PHYS_MASK_MSR(i));if ((maskm.lo & MTRR_PHYS_MASK_VALID) == 0)return i;}/* No free var mtrr */return -ENOSPC;+}
+int mtrr_set_next_var(uint type, uint64_t start, uint64_t size) +{
int mtrr;mtrr = get_free_var_mtrr();if (mtrr < 0)return mtrr;set_var_mtrr(mtrr, MTRR_TYPE_WRPROT, start, size);I think MTRR_TYPE_WRPROT should be parameter 'type'
Fixed this, and
debug("MTRR %x: start=%x, size=%x\n", mtrr, (uint)start, (uint)size);return 0;+} diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h index 6f29e75ce65..672617256e9 100644 --- a/arch/x86/include/asm/mtrr.h +++ b/arch/x86/include/asm/mtrr.h @@ -117,6 +117,18 @@ int mtrr_add_request(int type, uint64_t start, uint64_t size); */ int mtrr_commit(bool do_caches);
+/**
- mtrr_set_next_var() - set up a variable MTRR
- This finds the first free variable MTRR and sets to the given area
- @type: Requested type (MTRR_TYPE_)
- @start: Start address
- @size: Size
- @return 0 on success, -ENOSPC if there are no more MTRRs
- */
+int mtrr_set_next_var(uint type, uint64_t base, uint64_t size);
#endif
#if ((CONFIG_XIP_ROM_SIZE & (CONFIG_XIP_ROM_SIZE - 1)) != 0)
Other than above,
Reviewed-by: Bin Meng bmeng.cn@gmail.com
applied to u-boot-x86/next, thanks!