From e380f60b22eddec7825224b8d788572c82b63161 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 29 Oct 2010 18:11:26 +0100 Subject: agp/intel: Sandybridge doesn't require GMCH enabling Signed-off-by: Chris Wilson --- drivers/char/agp/intel-gtt.c | 37 ++++++++++++++++++++++++++++++------- 1 file changed, 30 insertions(+), 7 deletions(-) (limited to 'drivers/char') diff --git a/drivers/char/agp/intel-gtt.c b/drivers/char/agp/intel-gtt.c index 5dc1f5db55a7..9c86dac41da7 100644 --- a/drivers/char/agp/intel-gtt.c +++ b/drivers/char/agp/intel-gtt.c @@ -922,10 +922,11 @@ static void i830_write_entry(dma_addr_t addr, unsigned int entry, writel(addr | pte_flags, intel_private.gtt + entry); } -static void intel_enable_gtt(void) +static bool intel_enable_gtt(void) { u32 gma_addr; u16 gmch_ctrl; + u8 __iomem *reg; if (INTEL_GTT_GEN == 2) pci_read_config_dword(intel_private.pcidev, I810_GMADDR, @@ -936,13 +937,34 @@ static void intel_enable_gtt(void) intel_private.gma_bus_addr = (gma_addr & PCI_BASE_ADDRESS_MEM_MASK); - pci_read_config_word(intel_private.bridge_dev, I830_GMCH_CTRL, &gmch_ctrl); + if (INTEL_GTT_GEN >= 6) + return true; + + pci_read_config_word(intel_private.bridge_dev, + I830_GMCH_CTRL, &gmch_ctrl); gmch_ctrl |= I830_GMCH_ENABLED; - pci_write_config_word(intel_private.bridge_dev, I830_GMCH_CTRL, gmch_ctrl); + pci_write_config_word(intel_private.bridge_dev, + I830_GMCH_CTRL, gmch_ctrl); - writel(intel_private.PGETBL_save|I810_PGETBL_ENABLED, - intel_private.registers+I810_PGETBL_CTL); - readl(intel_private.registers+I810_PGETBL_CTL); /* PCI Posting. */ + pci_read_config_word(intel_private.bridge_dev, + I830_GMCH_CTRL, &gmch_ctrl); + if ((gmch_ctrl & I830_GMCH_ENABLED) == 0) { + dev_err(&intel_private.pcidev->dev, + "failed to enable the GTT: GMCH_CTRL=%x\n", + gmch_ctrl); + return false; + } + + reg = intel_private.registers+I810_PGETBL_CTL; + writel(intel_private.PGETBL_save|I810_PGETBL_ENABLED, reg); + if ((readl(reg) & I810_PGETBL_ENABLED) == 0) { + dev_err(&intel_private.pcidev->dev, + "failed to enable the GTT: PGETBL=%x [expected %x|1]\n", + readl(reg), intel_private.PGETBL_save); + return false; + } + + return true; } static int i830_setup(void) @@ -981,7 +1003,8 @@ static int intel_fake_agp_configure(void) { int i; - intel_enable_gtt(); + if (!intel_enable_gtt()) + return -EIO; agp_bridge->gart_bus_addr = intel_private.gma_bus_addr; -- cgit v1.2.3-55-g7522