[PATCH 4/4] mgag200: remove mgag200_probe_vram()

[Jocelyn Falempe]

This function writes some pattern to video memory, to check for conflict.
In case of conflicts, it returns a random memory capacity (offset of the
conflict).
Using devm_arch_io_reserve_memtype_wc() should garantee that no other
driver is using this memory region.
In case of real memory conflicts, as it is video memory, the user will
notice it easily. So there is no need for this function.

Signed-off-by: Jocelyn Falempe <jfalempe at redhat.com>
---
 drivers/gpu/drm/mgag200/mgag200_mm.c | 50 ++++------------------------
 1 file changed, 7 insertions(+), 43 deletions(-)

diff --git a/drivers/gpu/drm/mgag200/mgag200_mm.c b/drivers/gpu/drm/mgag200/mgag200_mm.c
index fa996d46feed..68299b560a98 100644
--- a/drivers/gpu/drm/mgag200/mgag200_mm.c
+++ b/drivers/gpu/drm/mgag200/mgag200_mm.c
@@ -32,48 +32,6 @@
 
 #include "mgag200_drv.h"
 
-static size_t mgag200_probe_vram(struct mga_device *mdev, void __iomem *mem,
-				 size_t size)
-{
-	int offset;
-	int orig;
-	int test1, test2;
-	int orig1, orig2;
-	size_t vram_size;
-
-	/* Probe */
-	orig = ioread16(mem);
-	iowrite16(0, mem);
-
-	vram_size = size;
-
-	if ((mdev->type == G200_EW3) && (vram_size >= 0x1000000))
-		vram_size = vram_size - 0x400000;
-
-	for (offset = 0x100000; offset < vram_size; offset += 0x4000) {
-		orig1 = ioread8(mem + offset);
-		orig2 = ioread8(mem + offset + 0x100);
-
-		iowrite16(0xaa55, mem + offset);
-		iowrite16(0xaa55, mem + offset + 0x100);
-
-		test1 = ioread16(mem + offset);
-		test2 = ioread16(mem);
-
-		iowrite16(orig1, mem + offset);
-		iowrite16(orig2, mem + offset + 0x100);
-
-		if (test1 != 0xaa55)
-			break;
-
-		if (test2)
-			break;
-	}
-
-	iowrite16(orig, mem);
-
-	return offset - 65536;
-}
 
 int mgag200_mm_init(struct mga_device *mdev)
 {
@@ -81,6 +39,7 @@ int mgag200_mm_init(struct mga_device *mdev)
 	struct pci_dev *pdev = to_pci_dev(dev->dev);
 	u8 misc;
 	resource_size_t start, len;
+	size_t vram_size;
 
 	WREG_ECRT(0x04, 0x00);
 
@@ -106,7 +65,12 @@ int mgag200_mm_init(struct mga_device *mdev)
 	if (!mdev->vram)
 		return -ENOMEM;
 
-	mdev->mc.vram_size = mgag200_probe_vram(mdev, mdev->vram, len);
+	vram_size = len;
+	/* G200_EW3 has only 12MB of memory */
+	if ((mdev->type == G200_EW3) && (vram_size >= 0x1000000))
+		vram_size -= 0x400000;
+
+	mdev->mc.vram_size = vram_size;
 	mdev->mc.vram_base = start;
 	mdev->mc.vram_window = len;
 
-- 
2.35.1