Re: [PULL v2 03/17] hw/loongarch: Add slave cpu boot_code

[chen huacai <zltjiangshi@gmail.com>]

On Thu, Mar 7, 2024 at 11:35 PM Song Gao <gaosong@loongson.cn> wrote:
>
> Signed-off-by: Song Gao <gaosong@loongson.cn>
> Message-Id: <20240301093839.663947-4-gaosong@loongson.cn>
> ---
>  hw/loongarch/boot.c | 70 ++++++++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 69 insertions(+), 1 deletion(-)
>
> diff --git a/hw/loongarch/boot.c b/hw/loongarch/boot.c
> index 3075c276d4..2f398260af 100644
> --- a/hw/loongarch/boot.c
> +++ b/hw/loongarch/boot.c
> @@ -14,6 +14,54 @@
>  #include "qemu/error-report.h"
>  #include "sysemu/reset.h"
>
> +static const unsigned int slave_boot_code[] = {
> +                  /* Configure reset ebase.         */
> +    0x0400302c,   /* csrwr      $r12,0xc            */
Use reg-names may be a little better than reg-nums.

Huacai
> +
> +                  /* Disable interrupt.             */
> +    0x0380100c,   /* ori        $r12,$r0,0x4        */
> +    0x04000180,   /* csrxchg    $r0,$r12,0x0        */
> +
> +                  /* Clear mailbox.                 */
> +    0x1400002d,   /* lu12i.w    $r13,1(0x1)         */
> +    0x038081ad,   /* ori        $r13,$r13,0x20      */
> +    0x06481da0,   /* iocsrwr.d  $r0,$r13            */
> +
> +                  /* Enable IPI interrupt.          */
> +    0x1400002c,   /* lu12i.w    $r12,1(0x1)         */
> +    0x0400118c,   /* csrxchg    $r12,$r12,0x4       */
> +    0x02fffc0c,   /* addi.d     $r12,$r0,-1(0xfff)  */
> +    0x1400002d,   /* lu12i.w    $r13,1(0x1)         */
> +    0x038011ad,   /* ori        $r13,$r13,0x4       */
> +    0x064819ac,   /* iocsrwr.w  $r12,$r13           */
> +    0x1400002d,   /* lu12i.w    $r13,1(0x1)         */
> +    0x038081ad,   /* ori        $r13,$r13,0x20      */
> +
> +                  /* Wait for wakeup  <.L11>:       */
> +    0x06488000,   /* idle       0x0                 */
> +    0x03400000,   /* andi       $r0,$r0,0x0         */
> +    0x064809ac,   /* iocsrrd.w  $r12,$r13           */
> +    0x43fff59f,   /* beqz       $r12,-12(0x7ffff4) # 48 <.L11> */
> +
> +                  /* Read and clear IPI interrupt.  */
> +    0x1400002d,   /* lu12i.w    $r13,1(0x1)         */
> +    0x064809ac,   /* iocsrrd.w  $r12,$r13           */
> +    0x1400002d,   /* lu12i.w    $r13,1(0x1)         */
> +    0x038031ad,   /* ori        $r13,$r13,0xc       */
> +    0x064819ac,   /* iocsrwr.w  $r12,$r13           */
> +
> +                  /* Disable  IPI interrupt.        */
> +    0x1400002c,   /* lu12i.w    $r12,1(0x1)         */
> +    0x04001180,   /* csrxchg    $r0,$r12,0x4        */
> +
> +                  /* Read mail buf and jump to specified entry */
> +    0x1400002d,   /* lu12i.w    $r13,1(0x1)         */
> +    0x038081ad,   /* ori        $r13,$r13,0x20      */
> +    0x06480dac,   /* iocsrrd.d  $r12,$r13           */
> +    0x00150181,   /* move       $r1,$r12            */
> +    0x4c000020,   /* jirl       $r0,$r1,0           */
> +};
> +
>  static uint64_t cpu_loongarch_virt_to_phys(void *opaque, uint64_t addr)
>  {
>      return addr & MAKE_64BIT_MASK(0, TARGET_PHYS_ADDR_SPACE_BITS);
> @@ -110,8 +158,15 @@ static void loongarch_firmware_boot(LoongArchMachineState *lams,
>      fw_cfg_add_kernel_info(info, lams->fw_cfg);
>  }
>
> +static void init_boot_rom(struct loongarch_boot_info *info, void *p)
> +{
> +    memcpy(p, &slave_boot_code, sizeof(slave_boot_code));
> +    p += sizeof(slave_boot_code);
> +}
> +
>  static void loongarch_direct_kernel_boot(struct loongarch_boot_info *info)
>  {
> +    void  *p, *bp;
>      int64_t kernel_addr = 0;
>      LoongArchCPU *lacpu;
>      CPUState *cs;
> @@ -123,11 +178,24 @@ static void loongarch_direct_kernel_boot(struct loongarch_boot_info *info)
>          exit(1);
>      }
>
> +    /* Load 'boot_rom' at [0 - 1MiB] */
> +    p = g_malloc0(1 * MiB);
> +    bp = p;
> +    init_boot_rom(info, p);
> +    rom_add_blob_fixed("boot_rom", bp, 1 * MiB, 0);
> +
>      CPU_FOREACH(cs) {
>          lacpu = LOONGARCH_CPU(cs);
>          lacpu->env.load_elf = true;
> -        lacpu->env.elf_address = kernel_addr;
> +        if (cs == first_cpu) {
> +            lacpu->env.elf_address = kernel_addr;
> +        } else {
> +            lacpu->env.elf_address = 0;
> +        }
> +        lacpu->env.boot_info = info;
>      }
> +
> +    g_free(bp);
>  }
>
>  void loongarch_load_kernel(MachineState *ms, struct loongarch_boot_info *info)
> --
> 2.34.1
>
>


-- 
Huacai Chen