diff options
| author | Arthur Heymans <arthur@aheymans.xyz> | 2022-05-06 17:04:41 +0200 |
|---|---|---|
| committer | Arthur Heymans <arthur@aheymans.xyz> | 2022-05-13 10:57:28 +0000 |
| commit | cc0b4527a69530c9a9a97aec265a84b85ca90ea2 (patch) | |
| tree | 58c825eecb2277d6eca7ce81d139bb61514576e3 /src/northbridge | |
| parent | 0cc56a2848e9558bcc63c5b68924ad46f4339804 (diff) | |
nb/intel/gm45/iommu.c: Fix clearing GTT
This was dead code as it was checking for the wrong bit (bit 11
indicates the use of shadow GTT). It was doing it at the wrong place
regardless as no BARs are set up.
Move the code clearing GTT into the GMA .init code and do it
unconditionally: if the GTT does not match 2M then the cycles are
simply not decoded.
Tested on thinkpad X200.
Change-Id: Iac3264d484e66e9ca4b3cd3df90ad87a476e31ce
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/64123
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
Diffstat (limited to 'src/northbridge')
| -rw-r--r-- | src/northbridge/intel/gm45/gma.c | 11 | ||||
| -rw-r--r-- | src/northbridge/intel/gm45/iommu.c | 17 |
2 files changed, 9 insertions, 19 deletions
diff --git a/src/northbridge/intel/gm45/gma.c b/src/northbridge/intel/gm45/gma.c index d5e9c48dc6..79b366f885 100644 --- a/src/northbridge/intel/gm45/gma.c +++ b/src/northbridge/intel/gm45/gma.c @@ -156,8 +156,15 @@ static void gma_func0_init(struct device *dev) return; mmio = res2mmio(gtt_res, 0, 0); - if (!CONFIG(NO_GFX_INIT)) - pci_or_config16(dev, PCI_COMMAND, PCI_COMMAND_MASTER); + /* + * GTT base is at a 2M offset and is 2M big. If GTT is smaller than 2M + * cycles are simply not decoded which is fine. + */ + pci_or_config16(dev, PCI_COMMAND, PCI_COMMAND_MASTER); + memset(mmio + 2 * MiB, 0, 2 * MiB); + + if (CONFIG(NO_GFX_INIT)) + pci_and_config16(dev, PCI_COMMAND, ~PCI_COMMAND_MASTER); if (!CONFIG(MAINBOARD_USE_LIBGFXINIT)) { /* PCI Init, will run VBIOS */ diff --git a/src/northbridge/intel/gm45/iommu.c b/src/northbridge/intel/gm45/iommu.c index 4199f8bb1d..4f6e000bdc 100644 --- a/src/northbridge/intel/gm45/iommu.c +++ b/src/northbridge/intel/gm45/iommu.c @@ -30,23 +30,6 @@ void init_iommu(void) } mchbar_write32(0x20, IOMMU_BASE4 | 1); /* all other DMA sources */ - /* clear GTT */ - u16 gtt = pci_read_config16(PCI_DEV(0, 0, 0), D0F0_GGC); - if (gtt & 0x400) { /* VT mode */ - const pci_devfn_t igd = PCI_DEV(0, 2, 0); - - /* setup somewhere */ - pci_or_config16(igd, PCI_COMMAND, PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY); - void *bar = (void *)pci_read_config32(igd, PCI_BASE_ADDRESS_0); - - /* clear GTT, 2MB is enough (and should be safe) */ - memset(bar, 0, 2<<20); - - /* and now disable again */ - pci_and_config16(igd, PCI_COMMAND, ~(PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY)); - pci_write_config32(igd, PCI_BASE_ADDRESS_0, 0); - } - if (stepping == STEPPING_B3) { mchbar_setbits8(0xffc, 1 << 4); const pci_devfn_t peg = PCI_DEV(0, 1, 0); |