[U-Boot] [PATCH v1 4/8] mpc8xxx: set x2 DDR3 refresh rate if SPD config requires it

Valentin Longchamp valentin.longchamp at keymile.com
Fri Jul 26 12:02:31 CEST 2013


If the DDR3 module supports industrial temperature range and requires
the x2 refresh rate for that temp range, the refresh period must be
3.9us instead of 7.8 us.

Signed-off-by: Valentin Longchamp <valentin.longchamp at keymile.com>
---
 arch/powerpc/cpu/mpc8xxx/ddr/ddr3_dimm_params.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/powerpc/cpu/mpc8xxx/ddr/ddr3_dimm_params.c b/arch/powerpc/cpu/mpc8xxx/ddr/ddr3_dimm_params.c
index 3e7c269..603b68b 100644
--- a/arch/powerpc/cpu/mpc8xxx/ddr/ddr3_dimm_params.c
+++ b/arch/powerpc/cpu/mpc8xxx/ddr/ddr3_dimm_params.c
@@ -320,6 +320,8 @@ ddr_compute_dimm_parameters(const ddr3_spd_eeprom_t *spd,
 	 *       = 3.9 us at ext temperature range
 	 */
 	pdimm->refresh_rate_ps = 7800000;
+	if ((spd->therm_ref_opt & 0x1) && !(spd->therm_ref_opt & 0x2))
+		pdimm->refresh_rate_ps = 3900000;
 
 	/*
 	 * min four active window delay time
-- 
1.8.0.1



More information about the U-Boot mailing list