[U-Boot] [PATCH 14/22] x86: Add support for MTRRs
Bin Meng
bmeng.cn at gmail.com
Wed Dec 31 04:24:36 CET 2014
Hi Simon,
On Sun, Dec 28, 2014 at 10:20 AM, Simon Glass <sjg at chromium.org> wrote:
> Memory Type Range Registers are used to tell the CPU whether memory is
> cacheable and if so the cache write mode to use.
>
> Clean up the existing header file to follow style, and remove the unneeded
> code.
>
> These can speed up booting so should be supported. Add these to global_data
> so they can be requested while booting. We will apply the changes during
> relocation (in a later commit).
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
>
> arch/x86/cpu/Makefile | 1 +
> arch/x86/cpu/coreboot/coreboot.c | 22 +++--
> arch/x86/cpu/ivybridge/car.S | 12 +--
> arch/x86/cpu/mtrr.c | 81 ++++++++++++++++++
> arch/x86/include/asm/global_data.h | 15 ++++
> arch/x86/include/asm/mtrr.h | 163 +++++++++++++++++--------------------
> 6 files changed, 186 insertions(+), 108 deletions(-)
> create mode 100644 arch/x86/cpu/mtrr.c
>
> diff --git a/arch/x86/cpu/Makefile b/arch/x86/cpu/Makefile
> index 5033d2b..62e43c0 100644
> --- a/arch/x86/cpu/Makefile
> +++ b/arch/x86/cpu/Makefile
> @@ -17,5 +17,6 @@ obj-$(CONFIG_NORTHBRIDGE_INTEL_SANDYBRIDGE) += ivybridge/
> obj-$(CONFIG_NORTHBRIDGE_INTEL_IVYBRIDGE) += ivybridge/
> obj-$(CONFIG_INTEL_QUEENSBAY) += queensbay/
> obj-y += lapic.o
> +obj-y += mtrr.o
> obj-$(CONFIG_PCI) += pci.o
> obj-y += turbo.o
> diff --git a/arch/x86/cpu/coreboot/coreboot.c b/arch/x86/cpu/coreboot/coreboot.c
> index cfacc05..6d06d5a 100644
> --- a/arch/x86/cpu/coreboot/coreboot.c
> +++ b/arch/x86/cpu/coreboot/coreboot.c
> @@ -15,6 +15,7 @@
> #include <asm/cache.h>
> #include <asm/cpu.h>
> #include <asm/io.h>
> +#include <asm/mtrr.h>
> #include <asm/arch/tables.h>
> #include <asm/arch/sysinfo.h>
> #include <asm/arch/timestamp.h>
> @@ -64,11 +65,6 @@ int board_eth_init(bd_t *bis)
> return pci_eth_init(bis);
> }
>
> -#define MTRR_TYPE_WP 5
> -#define MTRRcap_MSR 0xfe
> -#define MTRRphysBase_MSR(reg) (0x200 + 2 * (reg))
> -#define MTRRphysMask_MSR(reg) (0x200 + 2 * (reg) + 1)
> -
> void board_final_cleanup(void)
> {
> /* Un-cache the ROM so the kernel has one
> @@ -77,15 +73,17 @@ void board_final_cleanup(void)
> * Coreboot should have assigned this to the
> * top available variable MTRR.
> */
> - u8 top_mtrr = (native_read_msr(MTRRcap_MSR) & 0xff) - 1;
> - u8 top_type = native_read_msr(MTRRphysBase_MSR(top_mtrr)) & 0xff;
> + u8 top_mtrr = (native_read_msr(MTRR_CAP_MSR) & 0xff) - 1;
> + u8 top_type = native_read_msr(MTRR_PHYS_BASE_MSR(top_mtrr)) & 0xff;
>
> /* Make sure this MTRR is the correct Write-Protected type */
> - if (top_type == MTRR_TYPE_WP) {
> - disable_caches();
> - wrmsrl(MTRRphysBase_MSR(top_mtrr), 0);
> - wrmsrl(MTRRphysMask_MSR(top_mtrr), 0);
> - enable_caches();
> + if (top_type == MTRR_TYPE_WRPROT) {
> + struct mtrr_state state;
> +
> + mtrr_open(&state);
> + wrmsrl(MTRR_PHYS_BASE_MSR(top_mtrr), 0);
> + wrmsrl(MTRR_PHYS_MASK_MSR(top_mtrr), 0);
> + mtrr_close(&state);
> }
>
> /* Issue SMI to Coreboot to lock down ME and registers */
> diff --git a/arch/x86/cpu/ivybridge/car.S b/arch/x86/cpu/ivybridge/car.S
> index dca68e4..72b22ea 100644
> --- a/arch/x86/cpu/ivybridge/car.S
> +++ b/arch/x86/cpu/ivybridge/car.S
> @@ -61,7 +61,7 @@ clear_mtrrs:
>
> post_code(POST_CAR_MTRR)
> /* Configure the default memory type to uncacheable */
> - movl $MTRRdefType_MSR, %ecx
> + movl $MTRR_DEF_TYPE_MSR, %ecx
> rdmsr
> andl $(~0x00000cff), %eax
> wrmsr
> @@ -76,16 +76,16 @@ clear_mtrrs:
> post_code(POST_CAR_BASE_ADDRESS)
> /* Set Cache-as-RAM mask */
> movl $(MTRR_PHYS_MASK_MSR(0)), %ecx
> - movl $(~(CACHE_AS_RAM_SIZE - 1) | MTRRphysMaskValid), %eax
> + movl $(~(CACHE_AS_RAM_SIZE - 1) | MTRR_PHYS_MASK_VALID), %eax
> movl $CPU_PHYSMASK_HI, %edx
> wrmsr
>
> post_code(POST_CAR_MASK)
>
> /* Enable MTRR */
> - movl $MTRRdefType_MSR, %ecx
> + movl $MTRR_DEF_TYPE_MSR, %ecx
> rdmsr
> - orl $MTRRdefTypeEn, %eax
> + orl $MTRR_DEF_TYPE_EN, %eax
> wrmsr
>
> /* Enable cache (CR0.CD = 0, CR0.NW = 0) */
> @@ -130,7 +130,7 @@ clear_mtrrs:
>
> movl $MTRR_PHYS_MASK_MSR(1), %ecx
> movl $CPU_PHYSMASK_HI, %edx
> - movl $(~(CONFIG_XIP_ROM_SIZE - 1) | MTRRphysMaskValid), %eax
> + movl $(~(CONFIG_XIP_ROM_SIZE - 1) | MTRR_PHYS_MASK_VALID), %eax
> wrmsr
>
> post_code(POST_CAR_ROM_CACHE)
> @@ -141,7 +141,7 @@ clear_mtrrs:
> xorl %edx, %edx
> wrmsr
> movl $MTRR_PHYS_MASK_MSR(2), %ecx
> - movl $(CACHE_MRC_MASK | MTRRphysMaskValid), %eax
> + movl $(CACHE_MRC_MASK | MTRR_PHYS_MASK_VALID), %eax
> movl $CPU_PHYSMASK_HI, %edx
> wrmsr
> #endif
> diff --git a/arch/x86/cpu/mtrr.c b/arch/x86/cpu/mtrr.c
> new file mode 100644
> index 0000000..d5a825d1
> --- /dev/null
> +++ b/arch/x86/cpu/mtrr.c
> @@ -0,0 +1,81 @@
> +/*
> + * (C) Copyright 2014 Google, Inc
> + *
> + * SPDX-License-Identifier: GPL-2.0+
> + *
> + * Memory Type Range Regsters - these are used to tell the CPU whether
> + * memory is cacheable and if so the cache write mode to use.
> + *
> + * These can speed up booting. See the mtrr command.
> + *
> + * Reference: Intel Architecture Software Developer's Manual, Volume 3:
> + * System Programming
> + */
> +
> +#include <common.h>
> +#include <asm/io.h>
> +#include <asm/msr.h>
> +#include <asm/mtrr.h>
> +
> +/* Prepare to adjust MTRRs */
> +void mtrr_open(struct mtrr_state *state)
> +{
> + state->enable_cache = dcache_status();
> +
> + if (state->enable_cache)
> + disable_caches();
> + state->deftype = native_read_msr(MTRR_DEF_TYPE_MSR);
> + wrmsrl(MTRR_DEF_TYPE_MSR, state->deftype & ~MTRR_DEF_TYPE_EN);
> +}
> +
> +/* Clean up after adjusting MTRRs, and enable them */
> +void mtrr_close(struct mtrr_state *state)
> +{
> + wrmsrl(MTRR_DEF_TYPE_MSR, state->deftype | MTRR_DEF_TYPE_EN);
> + if (state->enable_cache)
> + enable_caches();
> +}
> +
> +int mtrr_commit(bool do_caches)
> +{
> + struct mtrr_request *req = gd->arch.mtrr_req;
> + struct mtrr_state state;
> + uint64_t mask;
> + int i;
> +
> + mtrr_open(&state);
> + for (i = 0; i < gd->arch.mtrr_req_count; i++, req++) {
> + mask = ~(req->size - 1);
> + mask &= (1ULL << CONFIG_CPU_ADDR_BITS) - 1;
> + wrmsrl(MTRR_PHYS_BASE_MSR(i), req->start | req->type);
> + wrmsrl(MTRR_PHYS_MASK_MSR(i), mask | MTRR_PHYS_MASK_VALID);
> + }
> +
> + /* Clear the ones that are unused */
> + for (; i < MTRR_COUNT; i++)
> + wrmsrl(MTRR_PHYS_MASK_MSR(i), 0);
> + mtrr_close(&state);
> +
> + return 0;
> +}
> +
> +int mtrr_add_request(int type, uint64_t start, uint64_t size)
> +{
> + struct mtrr_request *req;
> + uint64_t mask;
> +
> + if (gd->arch.mtrr_req_count == MAX_MTRR_REQUESTS)
> + return -ENOSPC;
> + req = &gd->arch.mtrr_req[gd->arch.mtrr_req_count++];
> + req->type = type;
> + req->start = start;
> + req->size = size;
> + debug("%d: type=%d, %08llx %08llx\n", gd->arch.mtrr_req_count - 1,
> + req->type, req->start, req->size);
> + mask = ~(req->size - 1);
> + mask &= (1ULL << CONFIG_CPU_ADDR_BITS) - 1;
> + mask |= MTRR_PHYS_MASK_VALID;
> + debug(" %016llx %016llx\n", req->start | req->type, mask);
> +
> + return 0;
> +}
> diff --git a/arch/x86/include/asm/global_data.h b/arch/x86/include/asm/global_data.h
> index 03d491a..15e76f6 100644
> --- a/arch/x86/include/asm/global_data.h
> +++ b/arch/x86/include/asm/global_data.h
> @@ -29,6 +29,19 @@ struct memory_info {
> struct memory_area area[CONFIG_NR_DRAM_BANKS];
> };
>
> +#define MAX_MTRR_REQUESTS 8
> +
> +/**
> + * A request for a memory region to be set up in a particular way. These
> + * requests are processed before board_init_r() is called. They are generally
> + * optional and can be ignored with some performance impact.
> + */
> +struct mtrr_request {
> + int type; /* MTRR_TYPE_... */
> + uint64_t start;
> + uint64_t size;
> +};
> +
> /* Architecture-specific global data */
> struct arch_global_data {
> struct global_data *gd_addr; /* Location of Global Data */
> @@ -50,6 +63,8 @@ struct arch_global_data {
> #ifdef CONFIG_HAVE_FSP
> void *hob_list; /* FSP HOB list */
> #endif
> + struct mtrr_request mtrr_req[MAX_MTRR_REQUESTS];
> + int mtrr_req_count;
> };
>
> #endif
> diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h
> index 5f05a48..3c11740 100644
> --- a/arch/x86/include/asm/mtrr.h
> +++ b/arch/x86/include/asm/mtrr.h
> @@ -9,99 +9,86 @@
> #ifndef _ASM_MTRR_H
> #define _ASM_MTRR_H
>
> -/* These are the region types */
> -#define MTRR_TYPE_UNCACHEABLE 0
> -#define MTRR_TYPE_WRCOMB 1
> -/*#define MTRR_TYPE_ 2*/
> -/*#define MTRR_TYPE_ 3*/
> -#define MTRR_TYPE_WRTHROUGH 4
> -#define MTRR_TYPE_WRPROT 5
> -#define MTRR_TYPE_WRBACK 6
> -#define MTRR_NUM_TYPES 7
> -
> -#define MTRRcap_MSR 0x0fe
> -#define MTRRdefType_MSR 0x2ff
> -
> -#define MTRRdefTypeEn (1 << 11)
> -#define MTRRdefTypeFixEn (1 << 10)
> -
> -#define SMRRphysBase_MSR 0x1f2
> -#define SMRRphysMask_MSR 0x1f3
> -
> -#define MTRRphysBase_MSR(reg) (0x200 + 2 * (reg))
> -#define MTRRphysMask_MSR(reg) (0x200 + 2 * (reg) + 1)
> -
> -#define MTRRphysMaskValid (1 << 11)
> -
> -#define NUM_FIXED_RANGES 88
> -#define RANGES_PER_FIXED_MTRR 8
> -#define MTRRfix64K_00000_MSR 0x250
> -#define MTRRfix16K_80000_MSR 0x258
> -#define MTRRfix16K_A0000_MSR 0x259
> -#define MTRRfix4K_C0000_MSR 0x268
> -#define MTRRfix4K_C8000_MSR 0x269
> -#define MTRRfix4K_D0000_MSR 0x26a
> -#define MTRRfix4K_D8000_MSR 0x26b
> -#define MTRRfix4K_E0000_MSR 0x26c
> -#define MTRRfix4K_E8000_MSR 0x26d
> -#define MTRRfix4K_F0000_MSR 0x26e
> -#define MTRRfix4K_F8000_MSR 0x26f
> +/* MTRR region types */
> +#define MTRR_TYPE_UNCACHEABLE 0
> +#define MTRR_TYPE_WRCOMB 1
> +#define MTRR_TYPE_WRTHROUGH 4
> +#define MTRR_TYPE_WRPROT 5
> +#define MTRR_TYPE_WRBACK 6
> +
> +#define MTRR_TYPE_COUNT 7
> +
> +#define MTRR_CAP_MSR 0x0fe
> +#define MTRR_DEF_TYPE_MSR 0x2ff
> +
> +#define MTRR_DEF_TYPE_EN (1 << 11)
> +#define MTRR_DEF_TYPE_FIX_EN (1 << 10)
> +
> +#define MTRR_PHYS_BASE_MSR(reg) (0x200 + 2 * (reg))
> +#define MTRR_PHYS_MASK_MSR(reg) (0x200 + 2 * (reg) + 1)
> +
> +#define MTRR_PHYS_MASK_VALID (1 << 11)
> +
> +#define MTRR_BASE_TYPE_MASK 0x7
> +
> +/* Number of MTRRs supported */
> +#define MTRR_COUNT 8
>
> #if !defined(__ASSEMBLER__)
>
> -/*
> - * The MTRR code has some side effects that the callers should be aware for.
> - * 1. The call sequence matters. x86_setup_mtrrs() calls
> - * x86_setup_fixed_mtrrs_no_enable() then enable_fixed_mtrrs() (equivalent
> - * of x86_setup_fixed_mtrrs()) then x86_setup_var_mtrrs(). If the callers
> - * want to call the components of x86_setup_mtrrs() because of other
> - * rquirements the ordering should still preserved.
> - * 2. enable_fixed_mtrr() will enable both variable and fixed MTRRs because
> - * of the nature of the global MTRR enable flag. Therefore, all direct
> - * or indirect callers of enable_fixed_mtrr() should ensure that the
> - * variable MTRR MSRs do not contain bad ranges.
> - * 3. If CONFIG_CACHE_ROM is selected an MTRR is allocated for enabling
> - * the caching of the ROM. However, it is set to uncacheable (UC). It
> - * is the responsiblity of the caller to enable it by calling
> - * x86_mtrr_enable_rom_caching().
> +/**
> + * Information about the previous MTRR state, set up by mtrr_open()
> + *
> + * @deftype: Previous value of MTRR_DEF_TYPE_MSR
> + * @enable_cache: true if cache was enabled
> */
> -void x86_setup_mtrrs(void);
> -/*
> - * x86_setup_var_mtrrs() parameters:
> - * address_bits - number of physical address bits supported by cpu
> - * above4gb - 2 means dynamically detect number of variable MTRRs available.
> - * non-zero means handle memory ranges above 4GiB.
> - * 0 means ignore memory ranges above 4GiB
> +struct mtrr_state {
> + uint64_t deftype;
> + bool enable_cache;
> +};
> +
> +/**
> + * mtrr_open() - Prepare to adjust MTRRs
> + *
> + * Use mtrr_open() passing in a structure - this function will init it. Then
> + * when done, pass the same structure to mtrr_close() to re-enable MTRRs and
> + * possibly the cache.
> + *
> + * @state: Empty structure to pass in to hold settings
> */
> -void x86_setup_var_mtrrs(unsigned int address_bits, unsigned int above4gb);
> -void enable_fixed_mtrr(void);
> -void x86_setup_fixed_mtrrs(void);
> -/* Set up fixed MTRRs but do not enable them. */
> -void x86_setup_fixed_mtrrs_no_enable(void);
> -int x86_mtrr_check(void);
> -/* ROM caching can be used after variable MTRRs are set up. Beware that
> - * enabling CONFIG_CACHE_ROM will eat through quite a few MTRRs based on
> - * one's IO hole size and WRCOMB resources. Be sure to check the console
> - * log when enabling CONFIG_CACHE_ROM or adding WRCOMB resources. Beware that
> - * on CPUs with core-scoped MTRR registers such as hyperthreaded CPUs the
> - * rom caching will be disabled if all threads run the MTRR code. Therefore,
> - * one needs to call x86_mtrr_enable_rom_caching() after all threads of the
> - * same core have run the MTRR code. */
> -#if CONFIG_CACHE_ROM
> -void x86_mtrr_enable_rom_caching(void);
> -void x86_mtrr_disable_rom_caching(void);
> -/* Return the variable range MTRR index of the ROM cache. */
> -long x86_mtrr_rom_cache_var_index(void);
> -#else
> -static inline void x86_mtrr_enable_rom_caching(void) {}
> -static inline void x86_mtrr_disable_rom_caching(void) {}
> -static inline long x86_mtrr_rom_cache_var_index(void) { return -1; }
> -#endif /* CONFIG_CACHE_ROM */
> +void mtrr_open(struct mtrr_state *state);
>
> -#endif
> +/**
> + * mtrr_open() - Clean up after adjusting MTRRs, and enable them
> + *
> + * This uses the structure containing information returned from mtrr_open().
> + *
> + * @state: Structure from mtrr_open()
> + */
> +/* */
> +void mtrr_close(struct mtrr_state *state);
> +
> +/**
> + * mtrr_add_request() - Add a new MTRR request
> + *
> + * This adds a request for a memory region to be set up in a particular way.
> + *
> + * @type: Requested type (MTRR_TYPE_)
> + * @start: Start address
> + * @size: Size
> + */
> +int mtrr_add_request(int type, uint64_t start, uint64_t size);
> +
> +/**
> + * mtrr_commit() - set up the MTRR registers based on current requests
> + *
> + * This sets up MTRRs for the available DRAM and the requests received so far.
> + * It must be called with caches disabled.
> + *
> + * @do_caches: true if caches are currently on
> + */
> +int mtrr_commit(bool do_caches);
>
> -#if !defined(CONFIG_RAMTOP)
> -# error "CONFIG_RAMTOP not defined"
> #endif
>
Can we move the removal of CONFIG_RAMTOP to the patch#2 in this series?
> #if ((CONFIG_XIP_ROM_SIZE & (CONFIG_XIP_ROM_SIZE - 1)) != 0)
> @@ -114,8 +101,4 @@ static inline long x86_mtrr_rom_cache_var_index(void) { return -1; }
>
> #define CACHE_ROM_BASE (((1 << 20) - (CONFIG_CACHE_ROM_SIZE >> 12)) << 12)
>
> -#if (CONFIG_RAMTOP & (CONFIG_RAMTOP - 1)) != 0
> -# error "CONFIG_RAMTOP must be a power of 2"
> -#endif
> -
Ditto.
> #endif
> --
Regards,
Bin
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