| Message ID | 20190925145750.200592-63-sjg@chromium.org |
|---|---|
| State | Accepted |
| Delegated to: | Bin Meng |
| Headers | show |
| Series | x86: Add initial support for apollolake | expand |
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' > + 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>
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!
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); + 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)
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(+)