[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-devel] Re: [PATCH 14/23] pci: factor out the logic to get pci devi
From: |
Michael S. Tsirkin |
Subject: |
[Qemu-devel] Re: [PATCH 14/23] pci: factor out the logic to get pci device from address. |
Date: |
Tue, 6 Oct 2009 12:23:13 +0200 |
User-agent: |
Mutt/1.5.19 (2009-01-05) |
On Tue, Oct 06, 2009 at 06:50:05PM +0900, Isaku Yamahata wrote:
> On Mon, Oct 05, 2009 at 02:45:33PM +0200, Michael S. Tsirkin wrote:
> > On Mon, Oct 05, 2009 at 07:06:54PM +0900, Isaku Yamahata wrote:
> > > factor out conversion logic from io port address into bus+dev+func
> > > with bit shift operation and conversion bus+dev+func into pci device.
> > > They will be used later by pcie support.
> > > This patch also eliminates the logic duplication.
> >
> > Please split removing logic duplication into separate patch.
> > It might be applicable already, while express stuff needs more work IMO.
> >
> > > Signed-off-by: Isaku Yamahata <address@hidden>
> > > ---
> > > hw/pci.c | 83
> > > ++++++++++++++++++++++++++++++++++---------------------------
> > > 1 files changed, 46 insertions(+), 37 deletions(-)
> > >
> > > diff --git a/hw/pci.c b/hw/pci.c
> > > index 6ddd256..5f808ff 100644
> > > --- a/hw/pci.c
> > > +++ b/hw/pci.c
> > > @@ -629,44 +629,25 @@ void pci_default_write_config(PCIDevice *d,
> > > uint32_t addr, uint32_t val, int l)
> > > pci_update_mappings(d);
> > > }
> > >
> > > -void pci_data_write(void *opaque, uint32_t addr, uint32_t val, int len)
> > > +static void pci_data_write_common(PCIDevice *pci_dev,
> > > + uint32_t config_addr, uint32_t val,
> > > int len)
> >
> > So as I said in the previous comment, pci express should just be able to
> > use pci code directly, instead of reusing this low-level stuff.
> > All you need to do is range-check address and ignore extended registers.
>
> Maybe my patch description isn't good enough,
> I'm afraid that you misunderstood the patch purpose.
>
> PCI configuration and PCI express MMCONFIG uses different address scheme
> as follows.
> This patch purpose is to separate out its address parsing logic
> from pci config space update logic.
>
> PCI:
> 0- 7 bit: offset in the configuration space (256bytes)
> 7-15 bit: devfn
> 16-14 bit: bus
>
> PCI express:
> 0-11 bit: offset in the configuration space (4KBytes)
> 12-19 bit: devfn
> 20-28 bit: bus
The comment is basically that there's no common code:
you don't need len checks that you added for mmconfig (they are there
just for documentation purposes), and so all pci_data_write does is
address parsing. So just call pci_dev->config_write for both mmconfig
and config.
> > > {
> > > - PCIBus *s = opaque;
> > > - PCIDevice *pci_dev;
> > > - int config_addr, bus_num;
> > > -
> > > -#if 0
> > > - PCI_DPRINTF("pci_data_write: addr=%08"PRIx32" val=%08"PRIx32"
> > > len=%d\n",
> > > - addr, val, len);
> > > -#endif
> > > - bus_num = (addr >> 16) & 0xff;
> > > - s = pci_find_bus(s, bus_num);
> > > - if (!s)
> > > - return;
> > > - pci_dev = s->devices[(addr >> 8) & 0xff];
> > > + assert(len == 1 || len == 2 || len == 4);
> > > if (!pci_dev)
> > > return;
> > > - config_addr = addr & 0xff;
> > > - PCI_DPRINTF("pci_config_write: %s: "
> > > - "addr=%02x val=%08"PRI32x" len=%d\n",
> > > - pci_dev->name, config_addr, val, len);
> > > +
> > > + PCI_DPRINTF("%s: %s: addr=%02"PRIx32" val=%08"PRI32x" len=%d\n",
> > > + __func__, pci_dev->name, config_addr, val, len);
> > > pci_dev->config_write(pci_dev, config_addr, val, len);
> > > }
> > >
> > > -uint32_t pci_data_read(void *opaque, uint32_t addr, int len)
> > > +static uint32_t pci_data_read_common(PCIDevice *pci_dev,
> > > + uint32_t config_addr, int len)
> > > {
> > > - PCIBus *s = opaque;
> > > - PCIDevice *pci_dev;
> > > - int config_addr, bus_num;
> > > uint32_t val;
> > >
> > > - bus_num = (addr >> 16) & 0xff;
> > > - s = pci_find_bus(s, bus_num);
> > > - if (!s)
> > > - goto fail;
> > > - pci_dev = s->devices[(addr >> 8) & 0xff];
> > > + assert(len == 1 || len == 2 || len == 4);
> > > if (!pci_dev) {
> > > - fail:
> > > switch(len) {
> > > case 1:
> > > val = 0xff;
> > > @@ -679,21 +660,49 @@ uint32_t pci_data_read(void *opaque, uint32_t addr,
> > > int len)
> > > val = 0xffffffff;
> > > break;
> > > }
> > > - goto the_end;
> > > + } else {
> > > + val = pci_dev->config_read(pci_dev, config_addr, len);
> > > + PCI_DPRINTF("%s: %s: addr=%02"PRIx32" val=%08"PRIx32" len=%d\n",
> > > + __func__, pci_dev->name, config_addr, val, len);
> > > }
> > > - config_addr = addr & 0xff;
> > > - val = pci_dev->config_read(pci_dev, config_addr, len);
> > > - PCI_DPRINTF("pci_config_read: %s: "
> > > - "addr=%02x val=%08"PRIx32" len=%d\n",
> > > - pci_dev->name, config_addr, val, len);
> > > - the_end:
> > > +
> > > #if 0
> > > - PCI_DPRINTF("pci_data_read: addr=%08"PRIx32" val=%08"PRIx32"
> > > len=%d\n",
> > > - addr, val, len);
> > > + PCI_DPRINTF("%s: addr=%08"PRIx32" val=%08"PRIx32" len=%d\n",
> > > + __func__, addr, val, len);
> > > #endif
> >
> > move to real pci_data_read?
> >
> > > return val;
> > > }
> > >
> > > +static inline PCIDevice *pci_addr_to_dev(PCIBus *bus, uint32_t addr)
> > > +{
> > > + uint8_t bus_num = (addr >> 16) & 0xff;
> > > + uint8_t devfn = (addr >> 8) & 0xff;
> > > + return pci_find_device(bus, bus_num, PCI_SLOT(devfn),
> > > PCI_FUNC(devfn));
> > > +}
> > > +
> > > +static inline uint32_t pci_addr_to_config(uint32_t addr)
> > > +{
> > > + return addr & 0xff;
> > > +}
> > > +
> > > +void pci_data_write(void *opaque, uint32_t addr, uint32_t val, int len)
> > > +{
> > > + PCIBus *s = opaque;
> > > +#if 0
> > > + PCI_DPRINTF("pci_data_write: addr=%08"PRIx32" val=%08"PRIx32"
> > > len=%d\n",
> > > + addr, val, len);
> > > +#endif
> > > +
> > > + pci_data_write_common(pci_addr_to_dev(s, addr),
> > > pci_addr_to_config(addr),
> > > + val, len);
> >
> > For pci express, there's extended register number in bits 11:8
> > so what we should do here IMO is check these bits and
> > ignore if they are not 0.
>
> I don't understand what you suggest.
> pci_data_{write, read}() are glue for ioio or mmio to
> access pci configuration space. And 'addr' parameter is used
> to specify configuration space access.
> It includes not only the offset in configuration space, but also
> devfn and bus.
>
Okay. I was misled by naming. What I am saying, here and elsewhere, is
that a large part of pain is because of 256 byte/4K byte difference.
Since in express you can hardware addresses > 256 to 0, I propose that
we simply make mmconfig code do this:
if (offset > 256)
return 0;
And then basically nothing needs to be changed in pci.
>
> > > +}
> > > +
> > > +uint32_t pci_data_read(void *opaque, uint32_t addr, int len)
> > > +{
> > > + PCIBus *s = opaque;
> >
> > For pci express, there's extended register number in bits 11:8
> > so what we should do here IMO is check these bits and
> > return 0 if not 0.
> >
> > > + return pci_data_read_common(pci_addr_to_dev(s, addr),
> > > + pci_addr_to_config(addr), len);
> > > +}
> > > /***********************************************************/
> > > /* generic PCI irq support */
> > >
> >
>
> --
> yamahata
- [Qemu-devel] Re: [PATCH 16/23] pci: pcie host and mmcfg support., (continued)
- [Qemu-devel] Re: [PATCH 16/23] pci: pcie host and mmcfg support., Michael S. Tsirkin, 2009/10/05
- [Qemu-devel] Re: [PATCH 16/23] pci: pcie host and mmcfg support., Isaku Yamahata, 2009/10/06
- [Qemu-devel] Re: [PATCH 16/23] pci: pcie host and mmcfg support., Michael S. Tsirkin, 2009/10/06
- [Qemu-devel] Re: [PATCH 16/23] pci: pcie host and mmcfg support., Michael S. Tsirkin, 2009/10/06
- [Qemu-devel] Re: [PATCH 16/23] pci: pcie host and mmcfg support., Isaku Yamahata, 2009/10/06
- [Qemu-devel] Re: [PATCH 16/23] pci: pcie host and mmcfg support., Michael S. Tsirkin, 2009/10/07
- Re: [Qemu-devel] Re: [PATCH 16/23] pci: pcie host and mmcfg support., Akio Takebe, 2009/10/07
[Qemu-devel] [PATCH 14/23] pci: factor out the logic to get pci device from address., Isaku Yamahata, 2009/10/05
[Qemu-devel] [PATCH 15/23] pci_host.h: split non-inline static function in pci_host.h into pci_host.c, Isaku Yamahata, 2009/10/05
[Qemu-devel] Re: [PATCH v4 00/23] pci: various pci clean up and pci express support., Michael S. Tsirkin, 2009/10/05
[Qemu-devel] Re: [PATCH v4 00/23] pci: various pci clean up and pci express support., Michael S. Tsirkin, 2009/10/06