intel-gtt: new function intel_gtt_mappable_entries

This implementation is stolen from drm/i915, but is equivalent to
the code sprinkled over intel-gtt.c in the various fetch_size functions.
It's not yet used anywhere, though.

Also introduce intel_gtt_init which only calls intel_gtt_stolen_entries.
Over the course of the next patches, this will grow untill it contains
the complete init sequence starting from the call to gtt_mappable_entries.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 59 insertions, 19 deletions

diff --git a/drivers/char/agp/intel-gtt.c b/drivers/char/agp/intel-gtt.c
index 9edeb060efb2..932ede81e726 100644
--- a/drivers/char/agp/intel-gtt.c
+++ b/drivers/char/agp/intel-gtt.c
@@ -755,6 +755,7 @@ static unsigned int intel_gtt_stolen_entries(void)
                         break;
                 }
         }
+
         if (!local && gtt_entries > intel_max_stolen) {
                 dev_info(&intel_private.bridge_dev->dev,
                          "detected %dK stolen memory, trimming to %dK\n",
@@ -773,6 +774,47 @@ static unsigned int intel_gtt_stolen_entries(void)
         return gtt_entries;
 }
 
+static unsigned int intel_gtt_mappable_entries(void)
+{
+        unsigned int aperture_size;
+        u16 gmch_ctrl;
+
+        aperture_size = 1024 * 1024;
+
+        pci_read_config_word(intel_private.bridge_dev,
+                             I830_GMCH_CTRL, &gmch_ctrl);
+
+        switch (intel_private.pcidev->device) {
+        case PCI_DEVICE_ID_INTEL_82830_CGC:
+        case PCI_DEVICE_ID_INTEL_82845G_IG:
+        case PCI_DEVICE_ID_INTEL_82855GM_IG:
+        case PCI_DEVICE_ID_INTEL_82865_IG:
+                if ((gmch_ctrl & I830_GMCH_MEM_MASK) == I830_GMCH_MEM_64M)
+                        aperture_size *= 64;
+                else
+                        aperture_size *= 128;
+                break;
+        default:
+                /* 9xx supports large sizes, just look at the length */
+                aperture_size = pci_resource_len(intel_private.pcidev, 2);
+                break;
+        }
+
+        return aperture_size >> PAGE_SHIFT;
+}
+
+static int intel_gtt_init(void)
+{
+        /* we have to call this as early as possible after the MMIO base address is known */
+        intel_private.base.gtt_stolen_entries = intel_gtt_stolen_entries();
+        if (intel_private.base.gtt_stolen_entries == 0) {
+                iounmap(intel_private.registers);
+                return -ENOMEM;
+        }
+
+        return 0;
+}
+
 static void intel_i830_fini_flush(void)
 {
         kunmap(intel_private.i8xx_page);
@@ -825,7 +867,7 @@ static void intel_i830_chipset_flush(struct agp_bridge_data *bridge)
  */
 static int intel_i830_create_gatt_table(struct agp_bridge_data *bridge)
 {
-        int page_order;
+        int page_order, ret;
         struct aper_size_info_fixed *size;
         int num_entries;
         u32 temp;
@@ -845,12 +887,9 @@ static int intel_i830_create_gatt_table(struct agp_bridge_data *bridge)
         temp = readl(intel_private.registers+I810_PGETBL_CTL) & 0xfffff000;
         global_cache_flush();   /* FIXME: ?? */
 
-        /* we have to call this as early as possible after the MMIO base address is known */
-        intel_private.base.gtt_stolen_entries = intel_gtt_stolen_entries();
-        if (intel_private.base.gtt_stolen_entries == 0) {
-                iounmap(intel_private.registers);
-                return -ENOMEM;
-        }
+        ret = intel_gtt_init();
+        if (ret != 0)
+                return ret;
 
         agp_bridge->gatt_table = NULL;
 
@@ -1302,7 +1341,7 @@ static int intel_i915_get_gtt_size(void)
  */
 static int intel_i915_create_gatt_table(struct agp_bridge_data *bridge)
 {
-        int page_order;
+        int page_order, ret;
         struct aper_size_info_fixed *size;
         int num_entries;
         u32 temp, temp2;
@@ -1335,12 +1374,10 @@ static int intel_i915_create_gatt_table(struct agp_bridge_data *bridge)
         temp = readl(intel_private.registers+I810_PGETBL_CTL) & 0xfffff000;
         global_cache_flush();   /* FIXME: ? */
 
-        /* we have to call this as early as possible after the MMIO base address is known */
-        intel_private.base.gtt_stolen_entries = intel_gtt_stolen_entries();
-        if (intel_private.base.gtt_stolen_entries == 0) {
+        ret = intel_gtt_init();
+        if (ret != 0) {
                 iounmap(intel_private.gtt);
-                iounmap(intel_private.registers);
-                return -ENOMEM;
+                return ret;
         }
 
         agp_bridge->gatt_table = NULL;
@@ -1426,7 +1463,7 @@ static void intel_i965_get_gtt_range(int *gtt_offset, int *gtt_size)
  */
 static int intel_i965_create_gatt_table(struct agp_bridge_data *bridge)
 {
-        int page_order;
+        int page_order, ret;
         struct aper_size_info_fixed *size;
         int num_entries;
         u32 temp;
@@ -1459,12 +1496,10 @@ static int intel_i965_create_gatt_table(struct agp_bridge_data *bridge)
         temp = readl(intel_private.registers+I810_PGETBL_CTL) & 0xfffff000;
         global_cache_flush();   /* FIXME: ? */
 
-        /* we have to call this as early as possible after the MMIO base address is known */
-        intel_private.base.gtt_stolen_entries = intel_gtt_stolen_entries();
-        if (intel_private.base.gtt_stolen_entries == 0) {
+        ret = intel_gtt_init();
+        if (ret != 0) {
                 iounmap(intel_private.gtt);
-                iounmap(intel_private.registers);
-                return -ENOMEM;
+                return ret;
         }
 
         agp_bridge->gatt_table = NULL;
@@ -1776,6 +1811,11 @@ int intel_gmch_probe(struct pci_dev *pdev,
                 pci_set_consistent_dma_mask(intel_private.pcidev,
                                             DMA_BIT_MASK(mask));
 
+        if (bridge->driver == &intel_810_driver)
+                return 1;
+
+        intel_private.base.gtt_mappable_entries = intel_gtt_mappable_entries();
+
         return 1;
 }
 EXPORT_SYMBOL(intel_gmch_probe);