[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-devel] Re: [PATCH 03/20] pci: simplify pci_data_read(), pcie_mmcfg
From: |
Michael S. Tsirkin |
Subject: |
[Qemu-devel] Re: [PATCH 03/20] pci: simplify pci_data_read(), pcie_mmcfg_data_read(). |
Date: |
Thu, 12 Nov 2009 13:15:25 +0200 |
User-agent: |
Mutt/1.5.19 (2009-01-05) |
On Thu, Nov 12, 2009 at 01:01:09PM +0200, Michael S. Tsirkin wrote:
> On Thu, Nov 12, 2009 at 02:58:31PM +0900, Isaku Yamahata wrote:
> > simplify ugly switch by memcpy trick.
> > And add one assert().
> >
> > Signed-off-by: Isaku Yamahata <address@hidden>
>
> In fact, there's no reason to be so careful about
> zeroing out high bits as far as I can tell:
> in the end, the value is assigned to uint32/uint16/uint8
> as appropriate and high bits are truncated.
> So this can simply be val = 0xffffffff;
>
> > ---
> > hw/pci_host.c | 16 ++++------------
> > hw/pcie_host.c | 16 ++++------------
> > 2 files changed, 8 insertions(+), 24 deletions(-)
> >
> > diff --git a/hw/pci_host.c b/hw/pci_host.c
> > index f4518dc..4196ebc 100644
> > --- a/hw/pci_host.c
> > +++ b/hw/pci_host.c
> > @@ -71,19 +71,11 @@ uint32_t pci_data_read(PCIBus *s, uint32_t addr, int
> > len)
> > uint32_t config_addr = pci_addr_to_config(addr);
> > uint32_t val;
> >
> > + assert(len == 1 || len == 2 || len == 4);
> > if (!pci_dev) {
> > - switch(len) {
> > - case 1:
> > - val = 0xff;
> > - break;
> > - case 2:
> > - val = 0xffff;
> > - break;
> > - default:
> > - case 4:
> > - val = 0xffffffff;
> > - break;
> > - }
> > + val = 0;
> > + memset(&val, 0xff, len);
> > + val = le32_to_cpu(val);
>
>
> So the above will become simply
> if (!pci_dev) {
> return ~0x0;
> }
>
>
> > } else {
> > val = pci_dev->config_read(pci_dev, config_addr, len);
> > PCI_DPRINTF("%s: %s: addr=%02"PRIx32" val=%08"PRIx32" len=%d\n",
> > diff --git a/hw/pcie_host.c b/hw/pcie_host.c
> > index b52fec6..61285da 100644
> > --- a/hw/pcie_host.c
> > +++ b/hw/pcie_host.c
> > @@ -71,19 +71,11 @@ static uint32_t pcie_mmcfg_data_read(PCIBus *s,
> > PCIDevice *pci_dev = pcie_mmcfg_addr_to_dev(s, mmcfg_addr);
> > uint32_t val;
> >
> > + assert(len == 1 || len == 2 || len == 4);
> > if (!pci_dev) {
> > - switch(len) {
> > - case 1:
> > - val = 0xff;
> > - break;
> > - case 2:
> > - val = 0xffff;
> > - break;
> > - default:
> > - case 4:
> > - val = 0xffffffff;
> > - break;
> > - }
> > + val = 0;
> > + memset(&val, 0xff, len);
> > + val = le32_to_cpu(val);
> > } else {
> > val = pci_dev->config_read(pci_dev,
> > PCIE_MMCFG_CONFOFFSET(mmcfg_addr), len);
> > --
> > 1.6.0.2
I put this on my tree instead:
--->
pci: simplify (pci_/pcie_mmcfg_)data_read()
Remove switch on length: we don't care about
high bits for value, so just return all ones
if no device. And add one assert().
Signed-off-by: Isaku Yamahata <address@hidden>
Signed-off-by: Michael S. Tsirkin <address@hidden>
---
diff --git a/hw/pci_host.c b/hw/pci_host.c
index f4518dc..4a29f44 100644
--- a/hw/pci_host.c
+++ b/hw/pci_host.c
@@ -71,25 +71,15 @@ uint32_t pci_data_read(PCIBus *s, uint32_t addr, int len)
uint32_t config_addr = pci_addr_to_config(addr);
uint32_t val;
+ assert(len == 1 || len == 2 || len == 4);
if (!pci_dev) {
- switch(len) {
- case 1:
- val = 0xff;
- break;
- case 2:
- val = 0xffff;
- break;
- default:
- case 4:
- val = 0xffffffff;
- break;
- }
- } 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);
+ return ~0x0;
}
+ 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);
+
return val;
}
diff --git a/hw/pcie_host.c b/hw/pcie_host.c
index b52fec6..9a5f135 100644
--- a/hw/pcie_host.c
+++ b/hw/pcie_host.c
@@ -65,31 +65,16 @@ static void pcie_mmcfg_data_write(PCIBus *s,
PCIE_MMCFG_CONFOFFSET(mmcfg_addr), val, len);
}
-static uint32_t pcie_mmcfg_data_read(PCIBus *s,
- uint32_t mmcfg_addr, int len)
+static uint32_t pcie_mmcfg_data_read(PCIBus *s, uint32_t addr, int len)
{
- PCIDevice *pci_dev = pcie_mmcfg_addr_to_dev(s, mmcfg_addr);
+ PCIDevice *pci_dev = pcie_mmcfg_addr_to_dev(s, addr);
uint32_t val;
+ assert(len == 1 || len == 2 || len == 4);
if (!pci_dev) {
- switch(len) {
- case 1:
- val = 0xff;
- break;
- case 2:
- val = 0xffff;
- break;
- default:
- case 4:
- val = 0xffffffff;
- break;
- }
- } else {
- val = pci_dev->config_read(pci_dev,
- PCIE_MMCFG_CONFOFFSET(mmcfg_addr), len);
+ return ~0x0;
}
-
- return val;
+ return pci_dev->config_read(pci_dev, PCIE_MMCFG_CONFOFFSET(addr), len);
}
static void pcie_mmcfg_data_writeb(void *opaque,
- [Qemu-devel] Re: [PATCH 15/20] pci: clean up of pci_update_mappings(), (continued)
- [Qemu-devel] [PATCH 02/20] pci: move pci_data_{read, write}() declaration from pci.h to pci_host.h, Isaku Yamahata, 2009/11/12
- [Qemu-devel] [PATCH 12/20] pci: remove some unnecessary comment in pci.h, Isaku Yamahata, 2009/11/12
- [Qemu-devel] [PATCH 08/20] pci: s/pci_find_host_bus/pci_find_root_bus/g, Isaku Yamahata, 2009/11/12
- [Qemu-devel] [PATCH 03/20] pci: simplify pci_data_read(), pcie_mmcfg_data_read()., Isaku Yamahata, 2009/11/12
[Qemu-devel] [PATCH 05/20] pci: rename pci_addr_to_dev(), pcie_mmcfg_addr_to_dev()., Isaku Yamahata, 2009/11/12
[Qemu-devel] [PATCH 11/20] pci: clean up of pci_init_wmask()., Isaku Yamahata, 2009/11/12
[Qemu-devel] [PATCH 07/20] pci: remove pci_sub_bus() by open coding., Isaku Yamahata, 2009/11/12
[Qemu-devel] [PATCH 18/20] pci: fix pci_config_get_io_base()., Isaku Yamahata, 2009/11/12