From 8098ed414ada4265f646e94d65eca063b3689f50 Mon Sep 17 00:00:00 2001 From: aurel32 Date: Thu, 18 Dec 2008 22:43:33 +0000 Subject: [PATCH] PCI: Mask writes to RO bits in the status reg of PCI config space The Status register in the PCI config space has some read-only bits. Any writes to those bits should be masked out. Signed-off-by: Amit Shah Signed-off-by: Aurelien Jarno git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6091 c046a42c-6fe2-441c-8c8c-71466251a162 --- hw/pci.c | 11 +++++++++++ hw/pci.h | 15 +++++++++++++++ 2 files changed, 26 insertions(+) diff --git a/hw/pci.c b/hw/pci.c index bf7db0db79..b95c79440c 100644 --- a/hw/pci.c +++ b/hw/pci.c @@ -381,6 +381,7 @@ void pci_default_write_config(PCIDevice *d, case 0x0b: case 0x0e: case 0x10 ... 0x27: /* base */ + case 0x2c ... 0x2f: /* read-only subsystem ID & vendor ID */ case 0x30 ... 0x33: /* rom */ case 0x3d: can_write = 0; @@ -402,6 +403,7 @@ void pci_default_write_config(PCIDevice *d, case 0x0a: case 0x0b: case 0x0e: + case 0x2c ... 0x2f: /* read-only subsystem ID & vendor ID */ case 0x38 ... 0x3b: /* rom */ case 0x3d: can_write = 0; @@ -413,6 +415,15 @@ void pci_default_write_config(PCIDevice *d, break; } if (can_write) { + /* Mask out writes to reserved bits in registers */ + switch (addr) { + case 0x06: + val &= ~PCI_STATUS_RESERVED_MASK_LO; + break; + case 0x07: + val &= ~PCI_STATUS_RESERVED_MASK_HI; + break; + } d->config[addr] = val; } if (++addr > 0xff) diff --git a/hw/pci.h b/hw/pci.h index 669703ebd6..95905db1ec 100644 --- a/hw/pci.h +++ b/hw/pci.h @@ -54,6 +54,21 @@ typedef struct PCIIORegion { #define PCI_MIN_GNT 0x3e /* 8 bits */ #define PCI_MAX_LAT 0x3f /* 8 bits */ +/* Bits in the PCI Status Register (PCI 2.3 spec) */ +#define PCI_STATUS_RESERVED1 0x007 +#define PCI_STATUS_INT_STATUS 0x008 +#define PCI_STATUS_CAPABILITIES 0x010 +#define PCI_STATUS_66MHZ 0x020 +#define PCI_STATUS_RESERVED2 0x040 +#define PCI_STATUS_FAST_BACK 0x080 +#define PCI_STATUS_DEVSEL 0x600 + +#define PCI_STATUS_RESERVED_MASK_LO (PCI_STATUS_RESERVED1 | \ + PCI_STATUS_INT_STATUS | PCI_STATUS_CAPABILITIES | \ + PCI_STATUS_66MHZ | PCI_STATUS_RESERVED2 | PCI_STATUS_FAST_BACK) + +#define PCI_STATUS_RESERVED_MASK_HI (PCI_STATUS_DEVSEL >> 8) + struct PCIDevice { /* PCI config space */ uint8_t config[256]; -- 2.34.1