[U-Boot] [PATCH 21/39] x86: chromebook_link: Implement CAR support (cache as RAM)
Bin Meng
bmeng.cn at gmail.com
Fri Nov 7 15:07:02 CET 2014
Hi Simon,
On Fri, Nov 7, 2014 at 4:20 AM, Simon Glass <sjg at chromium.org> wrote:
> Add support for CAR so that we have memory to use prior to DRAM init.
> On link there is a total of 128KB of CAR available, although some is
> used for the memory reference code.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
>
> arch/x86/Kconfig | 16 ++++
> arch/x86/cpu/ivybridge/car.S | 156 ++++++++++++++++++++++++++++++++++-
> arch/x86/cpu/ivybridge/cpu.c | 2 +
> arch/x86/include/asm/mtrr.h | 121 +++++++++++++++++++++++++++
> arch/x86/include/asm/post.h | 13 ++-
> board/google/chromebook_link/Kconfig | 12 +++
> 6 files changed, 318 insertions(+), 2 deletions(-)
> create mode 100644 arch/x86/include/asm/mtrr.h
>
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index d9ce129..73fe8b2 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -34,6 +34,22 @@ config TARGET_CHROMEBOOK_LINK
>
> endchoice
>
> +config RAMBASE
> + hex
> + default 0x100000
> +
> +config RAMTOP
> + hex
> + default 0x200000
> +
> +config XIP_ROM_SIZE
> + hex
> + default 0x10000
> +
> +config CPU_ADDR_BITS
> + int
> + default 36
> +
> config ROM_SIZE
> hex
> default 0x800000
> diff --git a/arch/x86/cpu/ivybridge/car.S b/arch/x86/cpu/ivybridge/car.S
> index 0480813..391f6df 100644
> --- a/arch/x86/cpu/ivybridge/car.S
> +++ b/arch/x86/cpu/ivybridge/car.S
> @@ -12,9 +12,163 @@
> */
>
> #include <common.h>
> +#include <asm/mtrr.h>
> +#include <asm/post.h>
> +#include <asm/processor-flags.h>
> +
> +#define MTRRphysBase_MSR(reg) (0x200 + 2 * (reg))
> +#define MTRRphysMask_MSR(reg) (0x200 + 2 * (reg) + 1)
Should these macros be all capital?
> +#define CACHE_AS_RAM_SIZE CONFIG_DCACHE_RAM_SIZE
> +#define CACHE_AS_RAM_BASE CONFIG_DCACHE_RAM_BASE
> +
> +/* Cache 4GB - MRC_SIZE_KB for MRC */
> +#define CACHE_MRC_BYTES ((CONFIG_CACHE_MRC_SIZE_KB << 10) - 1)
> +#define CACHE_MRC_BASE (0xFFFFFFFF - CACHE_MRC_BYTES)
> +#define CACHE_MRC_MASK (~CACHE_MRC_BYTES)
> +
> +#define CPU_PHYSMASK_HI (1 << (CONFIG_CPU_ADDR_BITS - 32) - 1)
> +
> +#define NoEvictMod_MSR 0x2e0
Ditto.
> /* Note: ebp must not be touched in this code */
I think mentioning ebp holds the value of BIST would help more?
> .globl car_init
> car_init:
> - /* TODO: Add cache-as-RAM init here */
> + post_code(POST_CAR_START)
> +
> + /* Send INIT IPI to all excluding ourself */
> + movl $0x000C4500, %eax
> + movl $0xFEE00300, %esi
> + movl %eax, (%esi)
> +
> + /* All CPUs need to be in Wait for SIPI state */
> +wait_for_sipi:
> + movl (%esi), %eax
> + bt $12, %eax
> + jc wait_for_sipi
Is this a must to send INIT IPI before CAR initialization?
> + post_code(POST_CAR_SIPI)
> + /* Zero out all fixed range and variable range MTRRs */
> + movl $mtrr_table, %esi
> + movl $((mtrr_table_end - mtrr_table) / 2), %edi
> + xorl %eax, %eax
> + xorl %edx, %edx
> +clear_mtrrs:
> + movw (%esi), %bx
> + movzx %bx, %ecx
> + wrmsr
> + add $2, %esi
> + dec %edi
> + jnz clear_mtrrs
> +
> + post_code(POST_CAR_MTRR)
> + /* Configure the default memory type to uncacheable */
> + movl $MTRRdefType_MSR, %ecx
> + rdmsr
> + andl $(~0x00000cff), %eax
> + wrmsr
> +
> + post_code(POST_CAR_UNCACHEABLE)
> + /* Set Cache-as-RAM base address */
> + movl $(MTRRphysBase_MSR(0)), %ecx
> + movl $(CACHE_AS_RAM_BASE | MTRR_TYPE_WRBACK), %eax
> + xorl %edx, %edx
> + wrmsr
> +
> + post_code(POST_CAR_BASE_ADDRESS)
> + /* Set Cache-as-RAM mask */
> + movl $(MTRRphysMask_MSR(0)), %ecx
> + movl $(~(CACHE_AS_RAM_SIZE - 1) | MTRRphysMaskValid), %eax
> + movl $CPU_PHYSMASK_HI, %edx
> + wrmsr
> +
> + post_code(POST_CAR_MASK)
> +
> + /* Enable MTRR */
> + movl $MTRRdefType_MSR, %ecx
> + rdmsr
> + orl $MTRRdefTypeEn, %eax
> + wrmsr
> +
> + /* Enable cache (CR0.CD = 0, CR0.NW = 0) */
> + movl %cr0, %eax
> + andl $(~(X86_CR0_CD | X86_CR0_NW)), %eax
> + invd
> + movl %eax, %cr0
> +
> + /* enable the 'no eviction' mode */
> + movl $NoEvictMod_MSR, %ecx
> + rdmsr
> + orl $1, %eax
> + andl $~2, %eax
> + wrmsr
> +
> + /* Clear the cache memory region. This will also fill up the cache */
> + movl $CACHE_AS_RAM_BASE, %esi
> + movl %esi, %edi
> + movl $(CACHE_AS_RAM_SIZE / 4), %ecx
> + xorl %eax, %eax
> + rep stosl
> +
> + /* enable the 'no eviction run' state */
> + movl $NoEvictMod_MSR, %ecx
> + rdmsr
> + orl $3, %eax
> + wrmsr
> +
> + post_code(POST_CAR_FILL)
> + /* Enable Cache-as-RAM mode by disabling cache */
> + movl %cr0, %eax
> + orl $X86_CR0_CD, %eax
> + movl %eax, %cr0
> +
> + /* Enable cache for our code in Flash because we do XIP here */
> + movl $MTRRphysBase_MSR(1), %ecx
> + xorl %edx, %edx
> + movl $car_init_ret, %eax
> + andl $(~(CONFIG_XIP_ROM_SIZE - 1)), %eax
> + orl $MTRR_TYPE_WRPROT, %eax
> + wrmsr
> +
> + movl $MTRRphysMask_MSR(1), %ecx
> + movl $CPU_PHYSMASK_HI, %edx
> + movl $(~(CONFIG_XIP_ROM_SIZE - 1) | MTRRphysMaskValid), %eax
> + wrmsr
> +
> + post_code(POST_CAR_ROM_CACHE)
> +#ifdef CONFIG_CACHE_MRC_BIN
> + /* Enable caching for ram init code to run faster */
> + movl $MTRRphysBase_MSR(2), %ecx
> + movl $(CACHE_MRC_BASE | MTRR_TYPE_WRPROT), %eax
> + xorl %edx, %edx
> + wrmsr
> + movl $MTRRphysMask_MSR(2), %ecx
> + movl $(CACHE_MRC_MASK | MTRRphysMaskValid), %eax
> + movl $CPU_PHYSMASK_HI, %edx
> + wrmsr
> +#endif
> +
> + post_code(POST_CAR_MRC_CACHE)
> + /* Enable cache */
> + movl %cr0, %eax
> + andl $(~(X86_CR0_CD | X86_CR0_NW)), %eax
> + movl %eax, %cr0
> +
> + post_code(POST_CAR_CPU_CACHE)
> +
> + /* return */
> jmp car_init_ret
> +
> +mtrr_table:
> + /* Fixed MTRRs */
> + .word 0x250, 0x258, 0x259
> + .word 0x268, 0x269, 0x26A
> + .word 0x26B, 0x26C, 0x26D
> + .word 0x26E, 0x26F
> + /* Variable MTRRs */
> + .word 0x200, 0x201, 0x202, 0x203
> + .word 0x204, 0x205, 0x206, 0x207
> + .word 0x208, 0x209, 0x20A, 0x20B
> + .word 0x20C, 0x20D, 0x20E, 0x20F
> + .word 0x210, 0x211, 0x212, 0x213
> +mtrr_table_end:
> diff --git a/arch/x86/cpu/ivybridge/cpu.c b/arch/x86/cpu/ivybridge/cpu.c
> index 7e77be6..a9884ca 100644
> --- a/arch/x86/cpu/ivybridge/cpu.c
> +++ b/arch/x86/cpu/ivybridge/cpu.c
> @@ -11,6 +11,7 @@
> */
>
> #include <common.h>
> +#include <asm/post.h>
> #include <asm/processor.h>
>
> DECLARE_GLOBAL_DATA_PTR;
> @@ -19,6 +20,7 @@ int arch_cpu_init(void)
> {
> int ret;
>
> + post_code(POST_CPU_INIT);
> timer_set_base(rdtsc());
>
> ret = x86_cpu_init_f();
> diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h
> new file mode 100644
> index 0000000..5f05a48
> --- /dev/null
> +++ b/arch/x86/include/asm/mtrr.h
> @@ -0,0 +1,121 @@
> +/*
> + * Copyright (c) 2014 Google, Inc
> + *
> + * From Coreboot file of the same name
> + *
> + * SPDX-License-Identifier: GPL-2.0+
> + */
> +
> +#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
Ditto.
> +#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().
> + */
> +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
> + */
> +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 */
> +
> +#endif
> +
> +#if !defined(CONFIG_RAMTOP)
> +# error "CONFIG_RAMTOP not defined"
> +#endif
> +
> +#if ((CONFIG_XIP_ROM_SIZE & (CONFIG_XIP_ROM_SIZE - 1)) != 0)
> +# error "CONFIG_XIP_ROM_SIZE is not a power of 2"
> +#endif
> +
> +#if ((CONFIG_CACHE_ROM_SIZE & (CONFIG_CACHE_ROM_SIZE - 1)) != 0)
> +# error "CONFIG_CACHE_ROM_SIZE is not a power of 2"
> +#endif
> +
> +#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
> +
> +#endif
> diff --git a/arch/x86/include/asm/post.h b/arch/x86/include/asm/post.h
> index 3371185..b203dc9 100644
> --- a/arch/x86/include/asm/post.h
> +++ b/arch/x86/include/asm/post.h
> @@ -13,9 +13,18 @@
> /* post codes which represent various stages of init */
> #define POST_START 0x1e
> #define POST_CAR_START 0x1f
> -
> +#define POST_CAR_SIPI 0x20
> +#define POST_CAR_MTRR 0x21
> +#define POST_CAR_UNCACHEABLE 0x22
> +#define POST_CAR_BASE_ADDRESS 0x23
> +#define POST_CAR_MASK 0x24
> +#define POST_CAR_FILL 0x25
> +#define POST_CAR_ROM_CACHE 0x26
> +#define POST_CAR_MRC_CACHE 0x27
> +#define POST_CAR_CPU_CACHE 0x28
> #define POST_START_STACK 0x29
> #define POST_START_DONE 0x2a
> +#define POST_CPU_INIT 0x2b
>
> /* Output a post code using al - value must be 0 to 0xff */
> #ifdef __ASSEMBLY__
> @@ -23,6 +32,8 @@
> movb $value, %al; \
> outb %al, $POST_PORT
> #else
> +#include <asm/io.h>
> +
> static inline void post_code(int code)
> {
> outb(code, POST_PORT);
> diff --git a/board/google/chromebook_link/Kconfig b/board/google/chromebook_link/Kconfig
> index 9c715ba..3a4f557 100644
> --- a/board/google/chromebook_link/Kconfig
> +++ b/board/google/chromebook_link/Kconfig
> @@ -12,6 +12,18 @@ config SYS_SOC
> config SYS_CONFIG_NAME
> default "chromebook_link"
>
> +config BOARD_SPECIFIC_OPTIONS # dummy
> + def_bool y
> + select CPU_INTEL_SOCKET_RPGA989
> + select NORTHBRIDGE_INTEL_IVYBRIDGE
> + select SOUTHBRIDGE_INTEL_C216
> + select HAVE_ACPI_RESUME
> + select MARK_GRAPHICS_MEM_WRCOMB
> +
> +config MMCONF_BASE_ADDRESS
> + hex
> + default 0xf0000000
> +
> config EARLY_POST_CROS_EC
> bool "Enable early post to Chrome OS EC"
> default y
> --
Regards,
Bin
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