agp/intel: Fix resume regression from 2d2430cf

On i915 [EeePCs] something scribles over the registers during suspend
and resume so we must save a copy of the PGETBL_CTL register programmed
by the BIOS and restore that upon resume.

Reported-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

diff --git a/drivers/char/agp/intel-gtt.c b/drivers/char/agp/intel-gtt.c
index 791582c..ebdeab2 100644 (file)
--- a/drivers/char/agp/intel-gtt.c
+++ b/drivers/char/agp/intel-gtt.c
@@ -98,6 +98,7 @@ static struct _intel_private {
        u8 __iomem *registers;
        phys_addr_t gtt_bus_addr;
        phys_addr_t gma_bus_addr;
+       phys_addr_t pte_bus_addr;
        u32 __iomem *gtt;               /* I915G */
        int num_dcache_entries;
        union {
@@ -896,11 +897,9 @@ static void intel_i830_chipset_flush(struct agp_bridge_data *bridge)
 
 static void intel_enable_gtt(void)
 {
-       u32 ptetbl_addr, gma_addr;
+       u32 gma_addr;
        u16 gmch_ctrl;
 
-       ptetbl_addr = readl(intel_private.registers+I810_PGETBL_CTL) & 0xfffff000;
-
        if (INTEL_GTT_GEN == 2)
                pci_read_config_dword(intel_private.pcidev, I810_GMADDR,
                                      &gma_addr);
@@ -914,7 +913,8 @@ static void intel_enable_gtt(void)
        gmch_ctrl |= I830_GMCH_ENABLED;
        pci_write_config_word(intel_private.bridge_dev, I830_GMCH_CTRL, gmch_ctrl);
 
-       writel(ptetbl_addr|I810_PGETBL_ENABLED, intel_private.registers+I810_PGETBL_CTL);
+       writel(intel_private.pte_bus_addr|I810_PGETBL_ENABLED,
+              intel_private.registers+I810_PGETBL_CTL);
        readl(intel_private.registers+I810_PGETBL_CTL); /* PCI Posting. */
 }
 
@@ -930,6 +930,8 @@ static int i830_setup(void)
                return -ENOMEM;
 
        intel_private.gtt_bus_addr = reg_addr + I810_PTE_BASE;
+       intel_private.pte_bus_addr =
+               readl(intel_private.registers+I810_PGETBL_CTL) & 0xfffff000;
 
        intel_i830_setup_flush();
 
@@ -1279,6 +1281,7 @@ static int i9xx_setup(void)
 
        if (INTEL_GTT_GEN == 3) {
                u32 gtt_addr;
+
                pci_read_config_dword(intel_private.pcidev,
                                      I915_PTEADDR, &gtt_addr);
                intel_private.gtt_bus_addr = gtt_addr;
@@ -1298,6 +1301,9 @@ static int i9xx_setup(void)
                intel_private.gtt_bus_addr = reg_addr + gtt_offset;
        }
 
+       intel_private.pte_bus_addr =
+               readl(intel_private.registers+I810_PGETBL_CTL) & 0xfffff000;
+
        intel_i9xx_setup_flush();
 
        return 0;