[Qemu-devel] Re: [PATCH V5 28/29] pci: initialize pci config headers depending it pci header type.

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

On Fri, Oct 09, 2009 at 03:29:01PM +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.

It was? Can you investigate please?
Spec says most of these are optional.

> Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
> ---
>  hw/cirrus_vga.c |    1 -
>  hw/pci.c        |   62 ++++++++++++++++++++++++++++++++++++++++++++++++------
>  hw/pci.h        |   33 +++++++++++++++++++++++++++++
>  3 files changed, 88 insertions(+), 8 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 3a17cd8..6b51bba 100644
> --- a/hw/pci.c
> +++ b/hw/pci.c
> @@ -430,14 +430,52 @@ static void pci_init_wmask(PCIDevice *dev)
>      int i;
>      int config_size = pci_config_size(dev);
>  
> +    pci_set_word(dev->wmask + PCI_COMMAND,
> +                 PCI_COMMAND_IO |
> +                 PCI_COMMAND_MEMORY |
> +                 PCI_COMMAND_MASTER |
> +                 PCI_COMMAND_SPECIAL |
> +                 PCI_COMMAND_INVALIDATE |
> +                 PCI_COMMAND_VGA_PALETTE |
> +                 PCI_COMMAND_PARITY |
> +                 PCI_COMMAND_WAIT |
> +                 PCI_COMMAND_SERR |
> +                 PCI_COMMAND_FAST_BACK |
> +                 PCI_COMMAND_INTX_DISABLE);

At least INTX disable must not be writeable unless
we implement the masking functionality, and we don't

> +
>      dev->wmask[PCI_CACHE_LINE_SIZE] = 0xff;
>      dev->wmask[PCI_INTERRUPT_LINE] = 0xff;
> -    dev->wmask[PCI_COMMAND] = PCI_COMMAND_IO | PCI_COMMAND_MEMORY
> -                              | PCI_COMMAND_MASTER;
> -    for (i = PCI_CONFIG_HEADER_SIZE; i < config_size; ++i)
> +
> +    for (i = PCI_CONFIG_HEADER_SIZE; i < config_size; i++)

I dislike this change. We don't use the old value so ++i
is cleaner.

>          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);
> +
> +    /* sec status isn't emulated (yet) */
> +    d->wmask[PCI_SEC_STATUS] = 0;

0 is default value. Replace with /* TODO: emulate PCI_SEC_STATUS */
 (which bits do we have to emulate there?)

> +    /* base and limit */
> +    d->wmask[PCI_IO_BASE] = PCI_IO_RANGE_MASK & 0xff;
> +    d->wmask[PCI_IO_LIMIT] = PCI_IO_RANGE_MASK & 0xff;


& 0xff not necessary.

> +    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_set_long(d->wmask + PCI_PREF_BASE_UPPER32, 0xffffffff);
> +    pci_set_long(d->wmask + PCI_PREF_LIMIT_UPPER32, 0xffffffff);
> +
> +    pci_set_word(d->wmask + PCI_BRIDGE_CONTROL, 0xffff);

Can we just memset(xxx, 0xff, yyy) the whole range,
and just clear a single byte that is 0?

> +}
> +
>  static void pci_config_alloc(PCIDevice *pci_dev)
>  {
>      int config_size = pci_config_size(pci_dev);
> @@ -462,7 +500,8 @@ 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) {
> @@ -479,9 +518,16 @@ 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;
> @@ -504,7 +550,8 @@ 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)
> @@ -1093,7 +1140,8 @@ 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 3cd93e9..a933ef1 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 */
> @@ -162,7 +170,25 @@ typedef struct PCIIORegion {
>  
>  /* Header type 1 (PCI-to-PCI bridges) */
>  #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_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_PREF_LIMIT_UPPER32  0x2c
> +#define PCI_IO_BASE_UPPER16     0x30    /* Upper half of I/O addresses */
> +#define PCI_IO_LIMIT_UPPER16    0x32
> +/* 0x34 same as for htype 0 */
> +/* 0x35-0x3b is reserved */
>  #define PCI_ROM_ADDRESS1        0x38    /* Same as PCI_ROM_ADDRESS, but for htype 1 */
> +/* 0x3c-0x3d are same as for htype 0 */
> +#define PCI_BRIDGE_CONTROL      0x3e
>  
>  /* Size of the standard PCI config header */
>  #define PCI_CONFIG_HEADER_SIZE 0x40
> @@ -370,6 +396,13 @@ 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.
> +                                 */
> +
>      /* pcie stuff */
>      int is_express;   /* is this device pci express?
>                         * initialization code needs to know this before
> -- 
> 1.6.0.2