pci/bridge: fix pci_bridge_reset()

The lower bits of base/limit registers is RO and shouldn't be zero
cleared on reset. This patch fixes it.
In fact, the default value of base/limit registers aren't specified
in the spec. And some bridges disable forwarding on reset instead of
zeroing base/limit registers.
So introduce one function to disable bridge forwarding so that
such bridges can use it. It will be used later.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Isaku Yamahata 2010-10-20 17:18:51 +09:00 committed by Michael S. Tsirkin
parent 6da6d29fa6
commit 0208def1ca
2 changed files with 43 additions and 6 deletions

View file

@ -151,6 +151,26 @@ void pci_bridge_write_config(PCIDevice *d,
}
}
void pci_bridge_disable_base_limit(PCIDevice *dev)
{
uint8_t *conf = dev->config;
pci_byte_test_and_set_mask(conf + PCI_IO_BASE,
PCI_IO_RANGE_MASK & 0xff);
pci_byte_test_and_clear_mask(conf + PCI_IO_LIMIT,
PCI_IO_RANGE_MASK & 0xff);
pci_word_test_and_set_mask(conf + PCI_MEMORY_BASE,
PCI_MEMORY_RANGE_MASK & 0xffff);
pci_word_test_and_clear_mask(conf + PCI_MEMORY_LIMIT,
PCI_MEMORY_RANGE_MASK & 0xffff);
pci_word_test_and_set_mask(conf + PCI_PREF_MEMORY_BASE,
PCI_PREF_RANGE_MASK & 0xffff);
pci_word_test_and_clear_mask(conf + PCI_PREF_MEMORY_LIMIT,
PCI_PREF_RANGE_MASK & 0xffff);
pci_set_word(conf + PCI_PREF_BASE_UPPER32, 0);
pci_set_word(conf + PCI_PREF_LIMIT_UPPER32, 0);
}
/* reset bridge specific configuration registers */
void pci_bridge_reset_reg(PCIDevice *dev)
{
@ -161,12 +181,28 @@ void pci_bridge_reset_reg(PCIDevice *dev)
conf[PCI_SUBORDINATE_BUS] = 0;
conf[PCI_SEC_LATENCY_TIMER] = 0;
conf[PCI_IO_BASE] = 0;
conf[PCI_IO_LIMIT] = 0;
pci_set_word(conf + PCI_MEMORY_BASE, 0);
pci_set_word(conf + PCI_MEMORY_LIMIT, 0);
pci_set_word(conf + PCI_PREF_MEMORY_BASE, 0);
pci_set_word(conf + PCI_PREF_MEMORY_LIMIT, 0);
/*
* the default values for base/limit registers aren't specified
* in the PCI-to-PCI-bridge spec. So we don't thouch them here.
* Each implementation can override it.
* typical implementation does
* zero base/limit registers or
* disable forwarding: pci_bridge_disable_base_limit()
* If disable forwarding is wanted, call pci_bridge_disable_base_limit()
* after this function.
*/
pci_byte_test_and_clear_mask(conf + PCI_IO_BASE,
PCI_IO_RANGE_MASK & 0xff);
pci_byte_test_and_clear_mask(conf + PCI_IO_LIMIT,
PCI_IO_RANGE_MASK & 0xff);
pci_word_test_and_clear_mask(conf + PCI_MEMORY_BASE,
PCI_MEMORY_RANGE_MASK & 0xffff);
pci_word_test_and_clear_mask(conf + PCI_MEMORY_LIMIT,
PCI_MEMORY_RANGE_MASK & 0xffff);
pci_word_test_and_clear_mask(conf + PCI_PREF_MEMORY_BASE,
PCI_PREF_RANGE_MASK & 0xffff);
pci_word_test_and_clear_mask(conf + PCI_PREF_MEMORY_LIMIT,
PCI_PREF_RANGE_MASK & 0xffff);
pci_set_word(conf + PCI_PREF_BASE_UPPER32, 0);
pci_set_word(conf + PCI_PREF_LIMIT_UPPER32, 0);

View file

@ -39,6 +39,7 @@ pcibus_t pci_bridge_get_limit(const PCIDevice *bridge, uint8_t type);
void pci_bridge_write_config(PCIDevice *d,
uint32_t address, uint32_t val, int len);
void pci_bridge_disable_base_limit(PCIDevice *dev);
void pci_bridge_reset_reg(PCIDevice *dev);
void pci_bridge_reset(DeviceState *qdev);