From bcb6c2bb84705bfd73eed5c9a31e9ff24833ee8c Mon Sep 17 00:00:00 2001
From: York Sun <yorksun@freescale.com>
Date: Fri, 7 May 2010 09:12:01 -0500
Subject: [PATCH] Enabled support for Rev 1.3 SPD for DDR2 DIMMs
SPD has minor change from Rev 1.2 to 1.3. This patch enables Rev 1.3.
The difference has ben examined and the code is compatible.
Speed bins is not verified on hardware for CL7 at this moment.
This patch also enables SPD Rev 1.x where x is up to "F". According to SPD
spec, the lower nibble is optionally used to determine which additinal bytes
or attribute bits have been defined. Software can safely use defaults. However,
the upper nibble should always be checked.
Signed-off-by: York Sun <yorksun@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
---
arch/powerpc/cpu/mpc8xxx/ddr/ddr2_dimm_params.c | 4 ++--
common/ddr_spd.c | 6 +++++-
2 files changed, 7 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/cpu/mpc8xxx/ddr/ddr2_dimm_params.c b/arch/powerpc/cpu/mpc8xxx/ddr/ddr2_dimm_params.c
index d9d0fa70eeb..dcb37cea1f9 100644
--- a/arch/powerpc/cpu/mpc8xxx/ddr/ddr2_dimm_params.c
+++ b/arch/powerpc/cpu/mpc8xxx/ddr/ddr2_dimm_params.c
@@ -175,8 +175,8 @@ determine_refresh_rate_ps(const unsigned int spd_refresh)
* ordinal 2, ddr2_speed_bins[1] contains tCK for CL=3
* Not certain if any good value exists for CL=2
*/
- /* CL2 CL3 CL4 CL5 CL6 */
-unsigned short ddr2_speed_bins[] = { 0, 5000, 3750, 3000, 2500 };
+ /* CL2 CL3 CL4 CL5 CL6 CL7*/
+unsigned short ddr2_speed_bins[] = { 0, 5000, 3750, 3000, 2500, 1875 };
unsigned int
compute_derated_DDR2_CAS_latency(unsigned int mclk_ps)
diff --git a/common/ddr_spd.c b/common/ddr_spd.c
index c058e4f18a3..a7a30de22bb 100644
--- a/common/ddr_spd.c
+++ b/common/ddr_spd.c
@@ -20,11 +20,15 @@ spd_check(const u8 *buf, u8 spd_rev, u8 spd_cksum)
* Check SPD revision supported
* Rev 1.2 or less supported by this code
*/
- if (spd_rev > 0x12) {
+ if (spd_rev >= 0x20) {
printf("SPD revision %02X not supported by this code\n",
spd_rev);
return 1;
}
+ if (spd_rev > 0x13) {
+ printf("SPD revision %02X not verified by this code\n",
+ spd_rev);
+ }
/*
* Calculate checksum
--
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