From e7cd070da61c1dc096aa8cd45185f90f6508707b Mon Sep 17 00:00:00 2001 From: Bin Meng Date: Wed, 22 Jul 2015 01:21:11 -0700 Subject: [PATCH] x86: qemu: Enable I/O APIC chip select on PIIX3 The PIIX3 chipset does not integrate an I/O APIC, instead it supports connecting to an external I/O APIC which needs to be enabled manually. Signed-off-by: Bin Meng Acked-by: Simon Glass --- arch/x86/cpu/qemu/pci.c | 7 ++++++- arch/x86/include/asm/arch-qemu/qemu.h | 6 +++++- 2 files changed, 11 insertions(+), 2 deletions(-) diff --git a/arch/x86/cpu/qemu/pci.c b/arch/x86/cpu/qemu/pci.c index 1a9140b46e..ab93e76054 100644 --- a/arch/x86/cpu/qemu/pci.c +++ b/arch/x86/cpu/qemu/pci.c @@ -50,7 +50,7 @@ void board_pci_setup_hose(struct pci_controller *hose) int board_pci_post_scan(struct pci_controller *hose) { int ret = 0; - u16 device; + u16 device, xbcs; int pam, i; pci_dev_t vga; ulong start; @@ -82,6 +82,11 @@ int board_pci_post_scan(struct pci_controller *hose) */ x86_pci_write_config16(PIIX_IDE, IDE0_TIM, IDE_DECODE_EN); x86_pci_write_config16(PIIX_IDE, IDE1_TIM, IDE_DECODE_EN); + + /* Enable I/O APIC */ + xbcs = x86_pci_read_config16(PIIX_ISA, XBCS); + xbcs |= APIC_EN; + x86_pci_write_config16(PIIX_ISA, XBCS, xbcs); } /* diff --git a/arch/x86/include/asm/arch-qemu/qemu.h b/arch/x86/include/asm/arch-qemu/qemu.h index 5cbfffffee..8c8e4ac1f6 100644 --- a/arch/x86/include/asm/arch-qemu/qemu.h +++ b/arch/x86/include/asm/arch-qemu/qemu.h @@ -13,10 +13,14 @@ #define PAM_NUM 7 #define PAM_RW 0x33 +/* X-Bus Chip Select Register */ +#define XBCS 0x4e +#define APIC_EN (1 << 8) + /* IDE Timing Register */ #define IDE0_TIM 0x40 #define IDE1_TIM 0x42 -#define IDE_DECODE_EN 0x8000 +#define IDE_DECODE_EN (1 << 15) /* I/O Ports */ #define CMOS_ADDR_PORT 0x70