Re: [Qemu-devel] [PATCH] Fix GPE registers read/write handling.

[Marcelo Tosatti <mtosatti@redhat.com>]

ACK

On Thu, Feb 12, 2009 at 10:10:31AM +0200, Gleb Natapov wrote:
> For STS register bit are cleared by writing 1 into it.
> 
> Signed-off-by: Gleb Natapov <gleb@redhat.com>
> ---
> 
>  hw/acpi.c |   43 +++++++++++++++++++++++++++++++------------
>  1 files changed, 31 insertions(+), 12 deletions(-)
> 
> diff --git a/hw/acpi.c b/hw/acpi.c
> index 630910a..5eac1ad 100644
> --- a/hw/acpi.c
> +++ b/hw/acpi.c
> @@ -579,22 +579,25 @@ struct pci_status {
>  static struct gpe_regs gpe;
>  static struct pci_status pci0_status;
>  
> +static uint32_t gpe_read_val(uint16_t val, uint32_t addr)
> +{
> +    if (addr & 1)
> +        return (val >> 8) & 0xff;
> +    return val & 0xff;
> +}
> +
>  static uint32_t gpe_readb(void *opaque, uint32_t addr)
>  {
>      uint32_t val = 0;
>      struct gpe_regs *g = opaque;
>      switch (addr) {
>          case GPE_BASE:
> -            val = g->sts & 0xFF;
> -            break;
>          case GPE_BASE + 1:
> -            val =  (g->sts >> 8) & 0xFF;
> +            val = gpe_read_val(g->sts, addr);
>              break;
>          case GPE_BASE + 2:
> -            val =  g->en & 0xFF;
> -            break;
>          case GPE_BASE + 3:
> -            val =  (g->en >> 8) & 0xFF;
> +            val = gpe_read_val(g->en, addr);
>              break;
>          default:
>              break;
> @@ -606,21 +609,37 @@ static uint32_t gpe_readb(void *opaque, uint32_t addr)
>      return val;
>  }
>  
> +static void gpe_write_val(uint16_t *cur, int addr, uint32_t val)
> +{
> +    if (addr & 1)
> +        *cur = (*cur & 0xff) | (val << 8);
> +    else
> +        *cur = (*cur & 0xff00) | (val & 0xff);
> +}
> +
> +static void gpe_reset_val(uint16_t *cur, int addr, uint32_t val)
> +{
> +    uint16_t x1, x0 = val & 0xff;
> +    int shift = (addr & 1) ? 8 : 0;
> +
> +    x1 = (*cur >> shift) & 0xff;
> +
> +    x1 = x1 & ~x0;
> +
> +    *cur = (*cur & (0xff << (8 - shift))) | (x1 << shift);
> +}
> +
>  static void gpe_writeb(void *opaque, uint32_t addr, uint32_t val)
>  {
>      struct gpe_regs *g = opaque;
>      switch (addr) {
>          case GPE_BASE:
> -            g->sts = (g->sts & ~0xFFFF) | (val & 0xFFFF);
> -            break;
>          case GPE_BASE + 1:
> -            g->sts = (g->sts & 0xFFFF) | (val << 8);
> +            gpe_reset_val(&g->sts, addr, val);
>              break;
>          case GPE_BASE + 2:
> -            g->en = (g->en & ~0xFFFF) | (val & 0xFFFF);
> -            break;
>          case GPE_BASE + 3:
> -            g->en = (g->en & 0xFFFF) | (val << 8);
> +            gpe_write_val(&g->en, addr, val);
>              break;
>          default:
>              break;
> 
>