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authorRonald G. Minnich <rminnich@google.com>2013-09-30 15:57:21 -0700
committerIsaac Christensen <isaac.christensen@se-eng.com>2014-08-26 01:23:24 +0200
commit4c8465cfac3a5b4bdc61e0f2f0bfb0b346b03ad2 (patch)
tree56602c0eebbb2a3cb59793f23c4847c18a9fae6f /src/northbridge/intel
parent8414d3c0b407d9afc6a2446dba3ca358da2c7bb6 (diff)
Peppy, Haswell: refactor and create set_translation_table function in haswell/gma.c
The code to set the graphics translation table has been in the mainboards, but should be in the northbridge support code. Move the function, give it a better name, and enable support for > 4 GiB while we're at it, in the remote possibility that we get some 8 GiB haswell boards. Change-Id: I72b4a0a88e53435e00d9b5e945479a51bd205130 Signed-off-by: Ronald G. Minnich <rminnich@google.com> Reviewed-on: https://chromium-review.googlesource.com/171160 Reviewed-by: Aaron Durbin <adurbin@chromium.org> Reviewed-by: Furquan Shaikh <furquan.m.shaikh@gmail.com> Commit-Queue: Ronald Minnich <rminnich@chromium.org> Tested-by: Ronald Minnich <rminnich@chromium.org> (cherry picked from commit d5a429498147c479eb51477927e146de809effce) Signed-off-by: Isaac Christensen <isaac.christensen@se-eng.com> Reviewed-on: http://review.coreboot.org/6741 Tested-by: build bot (Jenkins)
Diffstat (limited to 'src/northbridge/intel')
-rw-r--r--src/northbridge/intel/haswell/gma.c39
-rw-r--r--src/northbridge/intel/haswell/haswell.h1
2 files changed, 40 insertions, 0 deletions
diff --git a/src/northbridge/intel/haswell/gma.c b/src/northbridge/intel/haswell/gma.c
index 057d65ad55..8be25e785f 100644
--- a/src/northbridge/intel/haswell/gma.c
+++ b/src/northbridge/intel/haswell/gma.c
@@ -127,6 +127,45 @@ u32 map_oprom_vendev(u32 vendev)
return new_vendev;
}
+/* GTT is the Global Translation Table for the graphics pipeline.
+ * It is used to translate graphics addresses to physical
+ * memory addresses. As in the CPU, GTTs map 4K pages.
+ * The setgtt function adds a further bit of flexibility:
+ * it allows you to set a range (the first two parameters) to point
+ * to a physical address (third parameter);the physical address is
+ * incremented by a count (fourth parameter) for each GTT in the
+ * range.
+ * Why do it this way? For ultrafast startup,
+ * we can point all the GTT entries to point to one page,
+ * and set that page to 0s:
+ * memset(physbase, 0, 4096);
+ * setgtt(0, 4250, physbase, 0);
+ * this takes about 2 ms, and is a win because zeroing
+ * the page takes a up to 200 ms.
+ * This call sets the GTT to point to a linear range of pages
+ * starting at physbase.
+ */
+
+#define GTT_PTE_BASE (2 << 20)
+
+void
+set_translation_table(int start, int end, u64 base, int inc)
+{
+ int i;
+
+ for(i = start; i < end; i++){
+ u64 physical_address = base + i*inc;
+ /* swizzle the 32:39 bits to 4:11 */
+ u32 word = physical_address | ((physical_address >> 28) & 0xff0) | 1;
+ /* note: we've confirmed by checking
+ * the values that mrc does no
+ * useful setup before we run this.
+ */
+ gtt_write(GTT_PTE_BASE + i * 4, word);
+ gtt_read(GTT_PTE_BASE + i * 4);
+ }
+}
+
static struct resource *gtt_res = NULL;
u32 gtt_read(u32 reg)
diff --git a/src/northbridge/intel/haswell/haswell.h b/src/northbridge/intel/haswell/haswell.h
index bcd22d1be6..55f6f284e4 100644
--- a/src/northbridge/intel/haswell/haswell.h
+++ b/src/northbridge/intel/haswell/haswell.h
@@ -202,6 +202,7 @@ void intel_northbridge_haswell_finalize_smm(void);
#else /* !__SMM__ */
void haswell_early_initialization(int chipset_type);
void haswell_late_initialization(void);
+void set_translation_table(int start, int end, u64 base, int inc);
/* debugging functions */
void print_pci_devices(void);