Re: [PATCH v2 10/10] intel-gtt: Read 64bit for gmar_bus_addr

[Yinghai Lu <yinghai@xxxxxxxxxx>]

On Fri, Dec 20, 2013 at 4:27 PM, Bjorn Helgaas <bhelgaas@xxxxxxxxxx> wrote:

> Why are we reading these BARs directly anyway?  These look like
> standard PCI BARs (I810_GMADDR == 0x10 and I915_GMADDR == 0x18), so
> the PCI core should already be reading them correctly, shouldn't it?
> Can't we just use pcibios_resource_to_bus(pci_resource_start())?
>
> It looks like i810_setup(), i830_setup(), and i9xx_setup() have the
> same problem and should also be using pci_resource_start() or
> something similar.

Agreed.

should be sth like:


Index: linux-2.6/drivers/char/agp/intel-gtt.c
===================================================================
--- linux-2.6.orig/drivers/char/agp/intel-gtt.c
+++ linux-2.6/drivers/char/agp/intel-gtt.c
@@ -608,9 +608,9 @@ static bool intel_gtt_can_wc(void)

 static int intel_gtt_init(void)
 {
-       u32 gma_addr;
+       struct pci_bus_region r;
        u32 gtt_map_size;
-       int ret;
+       int ret, idx;

        ret = intel_private.driver->setup();
        if (ret != 0)
@@ -660,13 +660,14 @@ static int intel_gtt_init(void)
        }

        if (INTEL_GTT_GEN <= 2)
-               pci_read_config_dword(intel_private.pcidev, I810_GMADDR,
-                                     &gma_addr);
+               idx = 0; /* I810_GMADDR */
        else
-               pci_read_config_dword(intel_private.pcidev, I915_GMADDR,
-                                     &gma_addr);
+               idx = 2; /* I915_GMADDR */

-       intel_private.gma_bus_addr = (gma_addr & PCI_BASE_ADDRESS_MEM_MASK);
+       pcibios_resource_to_bus(intel_private.pcidev->bus, &r,
+                               &intel_private.pcidev->resource[idx]);
+
+       intel_private.gma_bus_addr = r.start;

        return 0;
 }

diff --git a/drivers/char/agp/intel-gtt.c b/drivers/char/agp/intel-gtt.c
index b8e2014..0250017 100644
--- a/drivers/char/agp/intel-gtt.c
+++ b/drivers/char/agp/intel-gtt.c
@@ -608,9 +608,9 @@ static bool intel_gtt_can_wc(void)
 
 static int intel_gtt_init(void)
 {
-	u32 gma_addr;
+	struct pci_bus_region r;
 	u32 gtt_map_size;
-	int ret;
+	int ret, idx;
 
 	ret = intel_private.driver->setup();
 	if (ret != 0)
@@ -660,13 +660,14 @@ static int intel_gtt_init(void)
 	}
 
 	if (INTEL_GTT_GEN <= 2)
-		pci_read_config_dword(intel_private.pcidev, I810_GMADDR,
-				      &gma_addr);
+		idx = 0; /* I810_GMADDR */
 	else
-		pci_read_config_dword(intel_private.pcidev, I915_GMADDR,
-				      &gma_addr);
+		idx = 2; /* I915_GMADDR */
+
+	pcibios_resource_to_bus(intel_private.pcidev->bus, &r,
+				&intel_private.pcidev->resource[idx]);
 
-	intel_private.gma_bus_addr = (gma_addr & PCI_BASE_ADDRESS_MEM_MASK);
+	intel_private.gma_bus_addr = r.start;
 
 	return 0;
 }