[Qemu-devel] Re: [PATCH V6 28/32] pci: initialize pci config headers depending it pci header type.

["Michael S. Tsirkin" <mst@redhat.com>]

On Fri, Oct 30, 2009 at 09:21:22PM +0900, Isaku Yamahata wrote:
> - Only sets default subsystem id for header type 00.(normal header type)
>   because header type 01 doesn't have subsystem id, and uses the register
>   for other purpose. So setting default subsystem id doesn't make sense.
> 
> - initialize wmask more for header type 01.(bridge header type)
>   Without those wmasks, linux was confused not boot,
>   and lspci was confused not to print out expected IO/memory range.
> 
> Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
> ---
>  hw/cirrus_vga.c |    1 -
>  hw/pci.c        |   42 ++++++++++++++++++++++++++++++++++++++----
>  hw/pci.h        |   29 +++++++++++++++++++++++++++++
>  3 files changed, 67 insertions(+), 5 deletions(-)
> 
> diff --git a/hw/cirrus_vga.c b/hw/cirrus_vga.c
> index ef72c62..c1bafd3 100644
> --- a/hw/cirrus_vga.c
> +++ b/hw/cirrus_vga.c
> @@ -180,7 +180,6 @@
>  #define PCI_COMMAND_PALETTESNOOPING         0x0020
>  #define PCI_COMMAND_PARITYDETECTION         0x0040
>  #define PCI_COMMAND_ADDRESSDATASTEPPING     0x0080
> -#define PCI_COMMAND_SERR                    0x0100
>  #define PCI_COMMAND_BACKTOBACKTRANS         0x0200
>  // PCI 0x08, 0xff000000 (0x09-0x0b:class,0x08:rev)
>  #define PCI_CLASS_BASE_DISPLAY        0x03
> diff --git a/hw/pci.c b/hw/pci.c
> index 46b22ec..beefae3 100644
> --- a/hw/pci.c
> +++ b/hw/pci.c
> @@ -445,6 +445,30 @@ static void pci_init_wmask(PCIDevice *dev)
>          dev->wmask[i] = 0xff;
>  }
>  
> +static void pci_init_wmask_bridge(PCIDevice *d)
> +{
> +    /* PCI_PRIMARY_BUS, PCI_SECONDARY_BUS, PCI_SUBORDINATE_BUS and
> +       PCI_SEC_LETENCY_TIMER */
> +    memset(d->wmask + PCI_PRIMARY_BUS, 0xff, 4);
> +
> +    /* base and limit */
> +    d->wmask[PCI_IO_BASE] = PCI_IO_RANGE_MASK & 0xff;
> +    d->wmask[PCI_IO_LIMIT] = PCI_IO_RANGE_MASK & 0xff;
> +    pci_set_word(d->wmask + PCI_MEMORY_BASE,
> +                 PCI_MEMORY_RANGE_MASK & 0xffff);
> +    pci_set_word(d->wmask + PCI_MEMORY_LIMIT,
> +                 PCI_MEMORY_RANGE_MASK & 0xffff);
> +    pci_set_word(d->wmask + PCI_PREF_MEMORY_BASE,
> +                 PCI_PREF_RANGE_MASK & 0xffff);
> +    pci_set_word(d->wmask + PCI_PREF_MEMORY_LIMIT,
> +                 PCI_PREF_RANGE_MASK & 0xffff);
> +
> +    /* PCI_PREF_BASE_UPPER32 and PCI_PREF_LIMIT_UPPER32 */
> +    memset(d->wmask + PCI_PREF_BASE_UPPER32, 0xff, 8);
> +
> +    pci_set_word(d->wmask + PCI_BRIDGE_CONTROL, 0xffff);
> +}
> +
>  static void pci_config_alloc(PCIDevice *pci_dev)
>  {
>      int config_size = pci_config_size(pci_dev);
> @@ -467,7 +491,8 @@ static void pci_config_free(PCIDevice *pci_dev)
>  static PCIDevice *do_pci_register_device(PCIDevice *pci_dev, PCIBus *bus,
>                                           const char *name, int devfn,
>                                           PCIConfigReadFunc *config_read,
> -                                         PCIConfigWriteFunc *config_write)
> +                                         PCIConfigWriteFunc *config_write,
> +                                         uint8_t header_type)
>  {
>      if (devfn < 0) {
>          for(devfn = bus->devfn_min ; devfn < 256; devfn += 8) {
> @@ -484,9 +509,16 @@ static PCIDevice *do_pci_register_device(PCIDevice *pci_dev, PCIBus *bus,
>      pstrcpy(pci_dev->name, sizeof(pci_dev->name), name);
>      memset(pci_dev->irq_state, 0, sizeof(pci_dev->irq_state));
>      pci_config_alloc(pci_dev);
> -    pci_set_default_subsystem_id(pci_dev);
> +
> +    header_type &= ~PCI_HEADER_TYPE_MULTI_FUNCTION;
> +    if (header_type == PCI_HEADER_TYPE_NORMAL) {
> +        pci_set_default_subsystem_id(pci_dev);
> +    }
>      pci_init_cmask(pci_dev);
>      pci_init_wmask(pci_dev);
> +    if (header_type == PCI_HEADER_TYPE_BRIDGE) {
> +        pci_init_wmask_bridge(pci_dev);
> +    }
>  
>      if (!config_read)
>          config_read = pci_default_read_config;

Instead of this, can we have pci_init_bridge that will simply
be called after device has been initialized?
Down the road we will be able to move it to pci_bridge.c


> @@ -509,7 +541,8 @@ PCIDevice *pci_register_device(PCIBus *bus, const char *name,
>  
>      pci_dev = qemu_mallocz(instance_size);
>      pci_dev = do_pci_register_device(pci_dev, bus, name, devfn,
> -                                     config_read, config_write);
> +                                     config_read, config_write,
> +                                     PCI_HEADER_TYPE_NORMAL);
>      return pci_dev;
>  }
>  static target_phys_addr_t pci_to_cpu_addr(target_phys_addr_t addr)
> @@ -1059,7 +1092,8 @@ static int pci_qdev_init(DeviceState *qdev, DeviceInfo *base)
>      bus = FROM_QBUS(PCIBus, qdev_get_parent_bus(qdev));
>      devfn = pci_dev->devfn;
>      pci_dev = do_pci_register_device(pci_dev, bus, base->name, devfn,
> -                                     info->config_read, info->config_write);
> +                                     info->config_read, info->config_write,
> +                                     info->header_type);
>      assert(pci_dev);
>      rc = info->init(pci_dev);
>      if (rc != 0)
> diff --git a/hw/pci.h b/hw/pci.h
> index 7991bfd..3f50294 100644
> --- a/hw/pci.h
> +++ b/hw/pci.h
> @@ -100,6 +100,14 @@ typedef struct PCIIORegion {
>  #define  PCI_COMMAND_IO		0x1	/* Enable response in I/O space */
>  #define  PCI_COMMAND_MEMORY	0x2	/* Enable response in Memory space */
>  #define  PCI_COMMAND_MASTER	0x4	/* Enable bus master */
> +#define  PCI_COMMAND_SPECIAL	0x8	/* Enable response to special cycles */
> +#define  PCI_COMMAND_INVALIDATE 0x10	/* Use memory write and invalidate */
> +#define  PCI_COMMAND_VGA_PALETTE 0x20	/* Enable palette snooping */
> +#define  PCI_COMMAND_PARITY	0x40	/* Enable parity checking */
> +#define  PCI_COMMAND_WAIT	0x80	/* Enable address/data stepping */
> +#define  PCI_COMMAND_SERR	0x100	/* Enable SERR */
> +#define  PCI_COMMAND_FAST_BACK	0x200	/* Enable back-to-back writes */
> +#define  PCI_COMMAND_INTX_DISABLE 0x400 /* INTx Emulation Disable */
>  #define PCI_STATUS              0x06    /* 16 bits */
>  #define PCI_REVISION_ID         0x08    /* 8 bits  */
>  #define PCI_CLASS_PROG		0x09	/* Reg. Level Programming Interface */
> @@ -119,16 +127,30 @@ typedef struct PCIIORegion {
>  #define PCI_PRIMARY_BUS		0x18	/* Primary bus number */
>  #define PCI_SECONDARY_BUS	0x19	/* Secondary bus number */
>  #define PCI_SUBORDINATE_BUS	0x1a	/* Highest bus number behind the bridge */
> +#define PCI_SEC_LATENCY_TIMER   0x1b    /* Latency timer for secondary interface */
> +#define PCI_IO_BASE             0x1c    /* I/O range behind the bridge */
> +#define PCI_IO_LIMIT            0x1d
> +#define  PCI_IO_RANGE_MASK      (~0x0fUL)
>  #define PCI_SEC_STATUS		0x1e	/* Secondary status register, only bit 14 used */
> +#define PCI_MEMORY_BASE         0x20    /* Memory range behind */
> +#define PCI_MEMORY_LIMIT        0x22
> +#define  PCI_MEMORY_RANGE_MASK  (~0x0fUL)
> +#define PCI_PREF_MEMORY_BASE    0x24    /* Prefetchable memory range behind */
> +#define PCI_PREF_MEMORY_LIMIT   0x26
> +#define  PCI_PREF_RANGE_MASK    (~0x0fUL)
> +#define PCI_PREF_BASE_UPPER32   0x28    /* Upper half of prefetchable memory range */
>  #define PCI_SUBSYSTEM_VENDOR_ID 0x2c    /* 16 bits */
>  #define PCI_SUBSYSTEM_ID        0x2e    /* 16 bits */
>  #define PCI_ROM_ADDRESS		0x30	/* Bits 31..11 are address, 10..1 reserved */
>  #define  PCI_ROM_ADDRESS_ENABLE	0x01
> +#define PCI_IO_BASE_UPPER16     0x30    /* Upper half of I/O addresses */
> +#define PCI_IO_LIMIT_UPPER16    0x32
>  #define PCI_CAPABILITY_LIST	0x34	/* Offset of first capability list entry */
>  #define PCI_ROM_ADDRESS1	0x38	/* Same as PCI_ROM_ADDRESS, but for htype 1 */
>  #define PCI_INTERRUPT_LINE	0x3c	/* 8 bits */
>  #define PCI_INTERRUPT_PIN	0x3d	/* 8 bits */
>  #define PCI_MIN_GNT		0x3e	/* 8 bits */
> +#define PCI_BRIDGE_CONTROL      0x3e
>  #define PCI_MAX_LAT		0x3f	/* 8 bits */
>  
>  /* Capability lists */


Many of these are unused. I'd rather we only defined what we use.

> @@ -358,6 +380,13 @@ typedef struct {
>      PCIConfigReadFunc *config_read;
>      PCIConfigWriteFunc *config_write;
>  
> +    /* pci config header type */
> +    uint8_t header_type;        /* this is necessary for initialization
> +                                 * code to know its header type before
> +                                 * device specific code can initialize
> +                                 * configuration space.
> +                                 */


The text probably belongs in commit comment.
Comments that tell how field is used quickly get out of date.
Say *what* it is is enough.

> +
>      /* pcie stuff */
>      int is_express;   /* is this device pci express?
>                         * initialization code needs to know this before
> -- 
> 1.6.0.2