Re: [U-Boot] [PATCH v2 5/5] x86: Switch to using generic global_data setup

On Tue, Aug 11, 2015 at 10:44 AM, Simon Glass sjg@chromium.org wrote:

There is quite a bit of assembler code that can be removed if we use the generic global_data setup. Less arch-specific code makes it easier to add new features and maintain the start-up code.

Drop the unneeded code and adjust the hooks in board_f.c to cope.

Signed-off-by: Simon Glass sjg@chromium.org

Changes in v2:

• Don't rely on value of %edx from board_init_f_mem()

arch/x86/cpu/cpu.c | 4 ++- arch/x86/cpu/start.S | 95 +++++++--------------------------------------------- common/board_f.c | 3 +- 3 files changed, 18 insertions(+), 84 deletions(-)

diff --git a/arch/x86/cpu/cpu.c b/arch/x86/cpu/cpu.c index 4f57145..1b76ca1 100644 --- a/arch/x86/cpu/cpu.c +++ b/arch/x86/cpu/cpu.c @@ -136,8 +136,10 @@ static void load_gdt(const u64 *boot_gdt, u16 num_entries) asm volatile("lgdtl %0\n" : : "m" (gdt)); }

-void setup_gdt(gd_t *new_gd, u64 *gdt_addr) +void arch_setup_gd(gd_t *new_gd) {

•   u64 *gdt_addr;
  

•   gdt_addr = new_gd->arch.gdt;
  
    /* CS: code, read/execute, 4 GB, base 0 */
  

diff --git a/arch/x86/cpu/start.S b/arch/x86/cpu/start.S index 313fa3f..e94ddc4 100644 --- a/arch/x86/cpu/start.S +++ b/arch/x86/cpu/start.S @@ -104,8 +104,7 @@ car_init_ret: * * top-> CONFIG_SYS_CAR_ADDR + CONFIG_SYS_CAR_SIZE * MRC area

•    *      global_data
  

•    *      x86 global descriptor table
  

•    *      global_data with x86 global descriptor table
     *      early malloc area
     *      stack
     * bottom-> CONFIG_SYS_CAR_ADDR
  

@@ -120,13 +119,10 @@ car_init_ret: * and esi holds the HOB list address returned by the FSP. */ #endif

•   /* Reserve space on stack for global data */
  

•   subl    $GENERATED_GBL_DATA_SIZE, %esp
  

•   /* Align global data to 16-byte boundary */
  

•   andl    $0xfffffff0, %esp
  

•   post_code(POST_START_STACK)
  

•   /* Set up global data */
  

•   mov     %esp, %eax
  

•   call    board_init_f_mem
  

•   mov     %eax, %esp
  
    /*
     * Debug UART is available here although it may not be plumbed out
  

@@ -137,56 +133,21 @@ car_init_ret: * call printch */

•   /* Zero the global data since it won't happen later */
  

•   xorl    %eax, %eax
  

•   movl    $GENERATED_GBL_DATA_SIZE, %ecx
  

•   movl    %esp, %edi
  

•   rep     stosb
  

•   /* Get address of global_data */
  

•   mov     %fs:0, %edx
  

#ifdef CONFIG_HAVE_FSP

•   /* Store the HOB list if we have one */
    test    %esi, %esi
    jz      skip_hob
  

•   /* Store HOB list */
  

•   movl    %esp, %edx
  

•   addl    $GD_HOB_LIST, %edx
  

•   movl    %esi, (%edx)
  

•   movl    %esi, GD_HOB_LIST(%edx)
  
  

skip_hob: #else /* Store table pointer */

•   movl    %esp, %edx
  

•   addl    $GD_TABLE, %edx
  

•   movl    %esi, (%edx)
  

•   movl    %esi, GD_TABLE(%edx)
  

#endif

•   /* Setup first parameter to setup_gdt, pointer to global_data */
  

•   movl    %esp, %eax
  

•   /* Reserve space for global descriptor table */
  

•   subl    $X86_GDT_SIZE, %esp
  

•   /* Align temporary global descriptor table to 16-byte boundary */
  

•   andl    $0xfffffff0, %esp
  

•   movl    %esp, %ecx
  

-#if defined(CONFIG_SYS_MALLOC_F_LEN)

•   /* Set up the pre-relocation malloc pool */
  

•   subl    $CONFIG_SYS_MALLOC_F_LEN, %esp
  

•   movl    %eax, %edx
  

•   addl    $GD_MALLOC_BASE, %edx
  

•   movl    %esp, (%edx)
  

-#endif

•   /* Store BIST into global_data */
  

•   movl    %eax, %edx
  

•   addl    $GD_BIST, %edx
  

•   movl    %ebp, (%edx)
  

•   /* Set second parameter to setup_gdt() */
  

•   movl    %ecx, %edx
  

•   /* Setup global descriptor table so gd->xyz works */
  

•   call    setup_gdt
  

•   /* Store BIST */
  

•   movl    %ebp, GD_BIST(%edx)
  
    /* Set parameter to board_init_f() to boot flags */
    post_code(POST_START_DONE)
  

@@ -213,37 +174,7 @@ board_init_f_r_trampoline: /* Stack grows down from top of SDRAM */ movl %eax, %esp

•   /* Reserve space on stack for global data */
  

•   subl    $GENERATED_GBL_DATA_SIZE, %esp
  

•   /* Align global data to 16-byte boundary */
  

•   andl    $0xfffffff0, %esp
  

•   /* Setup first parameter to memcpy() and setup_gdt() */
  

•   movl    %esp, %eax
  

•   /* Setup second parameter to memcpy() */
  

•   fs movl 0, %edx
  

•   /* Set third parameter to memcpy() */
  

•   movl    $GENERATED_GBL_DATA_SIZE, %ecx
  

•   /* Copy global data from CAR to SDRAM stack */
  

•   call    memcpy
  

•   /* Reserve space for global descriptor table */
  

•   subl    $X86_GDT_SIZE, %esp
  

•   /* Align global descriptor table to 16-byte boundary */
  

•   andl    $0xfffffff0, %esp
  

•   /* Set second parameter to setup_gdt() */
  

•   movl    %esp, %edx
  

•   /* Setup global descriptor table so gd->xyz works */
  

•   call    setup_gdt
  

•   /* Set if we need to disable CAR */
  

•   /* See if we need to disable CAR */
  

.weak car_uninit movl $car_uninit, %eax cmpl $0, %eax diff --git a/common/board_f.c b/common/board_f.c index 37b7bf5..c959774 100644 --- a/common/board_f.c +++ b/common/board_f.c @@ -715,6 +715,7 @@ static int jump_to_copy(void) * with the stack in SDRAM and Global Data in temporary memory * (CPU cache) */

•   arch_setup_gd(gd->new_gd);
    board_init_f_r_trampoline(gd->start_addr_sp);
  

#else relocate_code(gd->start_addr_sp, gd->new_gd, gd->relocaddr); @@ -1033,6 +1034,7 @@ __weak void arch_setup_gd(struct global_data *gd_ptr) { gd = gd_ptr; } +#endif /* !CONFIG_X86 */

ulong board_init_f_mem(ulong top) { @@ -1054,4 +1056,3 @@ ulong board_init_f_mem(ulong top)

    return top;

}

-#endif /* !CONFIG_X86 */

Reviewed-by: Bin Meng bmeng.cn@gmail.com