Commit f6bdfcc9 authored by Michael S. Tsirkin's avatar Michael S. Tsirkin
Browse files

pci: fix bridge control bit wmask 



Bits 12 to 15 in bridge control register are reserver and must be
read-only zero, curent mask is 0xffff which makes them writeable. Fix
this up by using symbolic bit names for writeable bits instead of a
hardcoded constant.

Fix a comment w1mask -> w1cmask as well.

Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
parent 09b926d4

hw/pci.c

+24 −2
Original line number Diff line number Diff line
@@ -558,7 +558,7 @@ static void pci_init_wmask(PCIDevice *dev) 
static void pci_init_w1cmask(PCIDevice *dev)

{

    /*

     * Note: It's okay to set w1mask even for readonly bits as

     * Note: It's okay to set w1cmask even for readonly bits as

     * long as their value is hardwired to 0.

     */

    pci_set_word(dev->w1cmask + PCI_STATUS,
@@ -588,7 +588,29 @@ static void pci_init_wmask_bridge(PCIDevice *d) 
    /* PCI_PREF_BASE_UPPER32 and PCI_PREF_LIMIT_UPPER32 */

    memset(d->wmask + PCI_PREF_BASE_UPPER32, 0xff, 8);



    pci_set_word(d->wmask + PCI_BRIDGE_CONTROL, 0xffff);

/* TODO: add this define to pci_regs.h in linux and then in qemu. */

#define  PCI_BRIDGE_CTL_VGA_16BIT	0x10	/* VGA 16-bit decode */

#define  PCI_BRIDGE_CTL_DISCARD		0x100	/* Primary discard timer */

#define  PCI_BRIDGE_CTL_SEC_DISCARD	0x200	/* Secondary discard timer */

#define  PCI_BRIDGE_CTL_DISCARD_STATUS	0x400	/* Discard timer status */

#define  PCI_BRIDGE_CTL_DISCARD_SERR	0x800	/* Discard timer SERR# enable */

    pci_set_word(d->wmask + PCI_BRIDGE_CONTROL,

                 PCI_BRIDGE_CTL_PARITY |

                 PCI_BRIDGE_CTL_SERR |

                 PCI_BRIDGE_CTL_ISA |

                 PCI_BRIDGE_CTL_VGA |

                 PCI_BRIDGE_CTL_VGA_16BIT |

                 PCI_BRIDGE_CTL_MASTER_ABORT |

                 PCI_BRIDGE_CTL_BUS_RESET |

                 PCI_BRIDGE_CTL_FAST_BACK |

                 PCI_BRIDGE_CTL_DISCARD |

                 PCI_BRIDGE_CTL_SEC_DISCARD |

                 PCI_BRIDGE_CTL_DISCARD_STATUS |

                 PCI_BRIDGE_CTL_DISCARD_SERR);

    /* Below does not do anything as we never set this bit, put here for

     * completeness. */

    pci_set_word(d->w1cmask + PCI_BRIDGE_CONTROL,

                 PCI_BRIDGE_CTL_DISCARD_STATUS);

}



static int pci_init_multifunction(PCIBus *bus, PCIDevice *dev)