From ba9b7bfc6f4b6622fa2d272faeb32b7135287ee6 Mon Sep 17 00:00:00 2001 From: Kane Chen Date: Sat, 17 Jan 2015 08:19:54 +0800 Subject: baytrail: add code for supporting 2x ddr refresh rate this code change provides a way to enable 2x refresh rate in RW image In baytrail, it enables 2x refresh rate by default BUG=chrome-os-partner:35210 BRANCH=none TEST=check the register is set properly on rambi Change-Id: I2a935b570c564986898b6c2064fc7ad43506dcba Signed-off-by: Stefan Reinauer Original-Commit-Id: c740d403708862514be9fa24f56b2764328979eb Original-Change-Id: I84f33d75ea7ebfea180b304e8ff683884f0dbe8a Original-Signed-off-by: Kane Chen Original-Reviewed-on: https://chromium-review.googlesource.com/241754 Original-Reviewed-by: Aaron Durbin Reviewed-on: http://review.coreboot.org/9498 Tested-by: build bot (Jenkins) Reviewed-by: Patrick Georgi --- src/soc/intel/baytrail/ramstage.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'src/soc/intel/baytrail/ramstage.c') diff --git a/src/soc/intel/baytrail/ramstage.c b/src/soc/intel/baytrail/ramstage.c index 6c2de111dc..8b6d93cbe0 100644 --- a/src/soc/intel/baytrail/ramstage.c +++ b/src/soc/intel/baytrail/ramstage.c @@ -38,6 +38,7 @@ #include #include #include +#include /* Global PATTRS */ DEFINE_PATTRS; @@ -170,12 +171,24 @@ static void s3_resume_prepare(void) s3_save_acpi_wake_source(gnvs); } +static void baytrail_enable_2x_refresh_rate(void) +{ + u32 reg; + reg = iosf_dunit_read(0x8); + reg = reg & ~0x7000; + reg = reg | 0x2000; + iosf_dunit_write(0x8, reg); +} + void baytrail_init_pre_device(struct soc_intel_baytrail_config *config) { struct soc_gpio_config *gpio_config; fill_in_pattrs(); + if (!config->disable_ddr_2x_refresh_rate) + baytrail_enable_2x_refresh_rate(); + /* Allow for SSE instructions to be executed. */ write_cr4(read_cr4() | CR4_OSFXSR | CR4_OSXMMEXCPT); -- cgit v1.2.3