[v8,01/11] pci: revise pci command register initialization

This patch cleans up command register initialization with
comments.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
---
 hw/pci.c |   42 ++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 42 insertions(+), 0 deletions(-)

On Mon, Nov 15, 2010 at 04:30:37PM +0900, Isaku Yamahata wrote:
> This patch cleans up command register initialization with
> comments.
> 
> Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>

Probably just fold with the next patch.

> ---
>  hw/pci.c |   42 ++++++++++++++++++++++++++++++++++++++++++
>  1 files changed, 42 insertions(+), 0 deletions(-)
> 
> diff --git a/hw/pci.c b/hw/pci.c
> index 962886e..b70a568 100644
> --- a/hw/pci.c
> +++ b/hw/pci.c
> @@ -544,8 +544,50 @@ static void pci_init_wmask(PCIDevice *dev)
>  
>      dev->wmask[PCI_CACHE_LINE_SIZE] = 0xff;
>      dev->wmask[PCI_INTERRUPT_LINE] = 0xff;
> +
> +    /*
> +     * bit 0: PCI_COMMAND_IO
> +     *        type 0: if IO BAR is used, RW
> +     *        type 1: RW
> +     * bit 1: PCI_COMMAND_MEMORY
> +     *        type 0: if IO BAR is used, RW
> +     *        type 1: RW
> +     * bit 2: PCI_COMMAND_MASTER
> +     *        type 0: RW if bus master
> +     *        type 1: RW
> +     * bit 3: PCI_COMMAND_SPECIAL
> +     *        RO=0, optionally RW: Such device should set this bit itself
> +     * bit 4: PCI_COMMAND_INVALIDATE
> +     *        RO=0, optionally RW: Such device should set this bit itself
> +     * bit 5: PCI_COMMAND_VGA_PALETTE
> +     *        RO=0, optionally RW: Such device should set this bit itself
> +     * bit 6: PCI_COMMAND_PARITY
> +     *        RW with exceptions: Such device should clear this bit itself
> +     *        Given that qemu doesn't emulate pci bus cycles, so that there
> +     *        is no place to generate parity error. So just making this
> +     *        register RW is okay because there is no place which refers
> +     *        this bit.
> +     *        TODO: When device assignment tried to inject PERR# into qemu,
> +     *              some extra work would be needed.
> +     * bit 7: PCI_COMMAND_WAIT: reserved (PCI 3.0)
> +     *        RO=0
> +     * bit 8: PCI_COMMAND_SERR
> +     *        RW with exceptions: Such device should clear this bit itself
> +     *        Given that qemu doesn't emulate pci bus cycles, so that there
> +     *        is no place to generate system error. So just making this
> +     *        register RW is okay because there is no place which refers
> +     *        this bit.
> +     *        TODO: When device assignment tried to inject SERR# into qemu,
> +     *              some extra work would be needed.
> +     * bit 9: PCI_COMMAND_FAST_BACK
> +     *        RO=0, optionally RW: Such device should set this bit itself
> +     * bit 10: PCI_COMMAND_INTX_DISABLE
> +     *         RW
> +     * bit 11-15: reserved
> +     */
>      pci_set_word(dev->wmask + PCI_COMMAND,
>                   PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER |
> +                 PCI_COMMAND_PARITY | PCI_COMMAND_SERR |
>                   PCI_COMMAND_INTX_DISABLE);
>  
>      memset(dev->wmask + PCI_CONFIG_HEADER_SIZE, 0xff,
> -- 
> 1.7.1.1