From 8ab91d875b3572a1c9b50e2035edf996aa8727da Mon Sep 17 00:00:00 2001 From: Uwe Hermann Date: Tue, 18 Nov 2008 12:02:03 +0000 Subject: i810: Add some more comments, and especially add a list of tested BUFF_SC values for different DIMM configurations. This should be converted to a table or code later on and actually be used for BUFF_SC. Many thanks to Elia Yehuda for testing and collecting the table entries. Signed-off-by: Uwe Hermann Acked-by: Uwe Hermann git-svn-id: svn://svn.coreboot.org/coreboot/trunk@3759 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1 --- src/northbridge/intel/i82810/i82810.h | 19 +++++++------ src/northbridge/intel/i82810/raminit.c | 49 +++++++++++++++++++++++++--------- 2 files changed, 46 insertions(+), 22 deletions(-) diff --git a/src/northbridge/intel/i82810/i82810.h b/src/northbridge/intel/i82810/i82810.h index e70b35c9a6..94993ec540 100644 --- a/src/northbridge/intel/i82810/i82810.h +++ b/src/northbridge/intel/i82810/i82810.h @@ -30,17 +30,16 @@ /* * PCI Configuration Registers. * - * Any addresses between 0x00 and 0xff not listed below are reserved and + * Any addresses between 0x50 and 0xff not listed below are reserved and * should not be touched. */ -/* TODO: Descriptions. */ -#define GMCHCFG 0x50 -#define PAM 0x51 -#define DRP 0x52 -#define DRAMT 0x53 -#define FDHC 0x58 +#define GMCHCFG 0x50 /* GMCH Configuration */ +#define PAM 0x51 /* Programmable Attributes */ +#define DRP 0x52 /* DRAM Row Population */ +#define DRAMT 0x53 /* DRAM Timing */ +#define FDHC 0x58 /* Fixed DRAM Hole Control */ #define SMRAM 0x70 /* System Management RAM Control */ -#define MISSC 0x72 -#define MISSC2 0x80 -#define BUFF_SC 0x92 +#define MISSC 0x72 /* Miscellaneous Control */ +#define MISSC2 0x80 /* Miscellaneous Control 2 */ +#define BUFF_SC 0x92 /* System Memory Buffer Strength Control */ diff --git a/src/northbridge/intel/i82810/raminit.c b/src/northbridge/intel/i82810/raminit.c index 67addf6caf..23d45c924f 100644 --- a/src/northbridge/intel/i82810/raminit.c +++ b/src/northbridge/intel/i82810/raminit.c @@ -47,13 +47,13 @@ Macros and definitions. #endif /* DRAMT[7:5] - SDRAM Mode Select (SMS). */ -#define RAM_COMMAND_SELF_REFRESH 0x0 /* IE disable refresh */ -#define RAM_COMMAND_NORMAL 0x1 /* Normal refresh, 15.6us/11.7us for 100/133MHz */ -#define RAM_COMMAND_NORMAL_FR 0x2 /* Fast refresh, 7.8us/5.85us for 100/133MHz */ -#define RAM_COMMAND_NOP 0x4 -#define RAM_COMMAND_PRECHARGE 0x5 -#define RAM_COMMAND_MRS 0x6 -#define RAM_COMMAND_CBR 0x7 +#define RAM_COMMAND_SELF_REFRESH 0x0 /* Disable refresh */ +#define RAM_COMMAND_NORMAL 0x1 /* Refresh: 15.6/11.7us for 100/133MHz */ +#define RAM_COMMAND_NORMAL_FR 0x2 /* Refresh: 7.8/5.85us for 100/133MHz */ +#define RAM_COMMAND_NOP 0x4 /* NOP command */ +#define RAM_COMMAND_PRECHARGE 0x5 /* All bank precharge */ +#define RAM_COMMAND_MRS 0x6 /* Mode register set */ +#define RAM_COMMAND_CBR 0x7 /* CBR */ /*----------------------------------------------------------------------------- SDRAM configuration functions. @@ -98,6 +98,9 @@ static void do_ram_command(const struct mem_controller *ctrl, uint32_t command, DIMM-independant configuration functions. -----------------------------------------------------------------------------*/ +/* + * Set DRP - DRAM Row Population Register (Device 0). + */ static void spd_set_dram_size(const struct mem_controller *ctrl, uint32_t row_offset) { @@ -209,13 +212,35 @@ static void set_dram_timing(const struct mem_controller *ctrl) // pci_write_config8(ctrl->d0, DRAMT, 0x00); } +/* + * TODO: BUFF_SC needs to be set according to the DRAM tech (x8, x16, + * or x32), but the datasheet doesn't list all the detaisl. Currently, it + * needs to be pulled from the output of 'lspci -xxx Rx92'. + * + * Common results (tested on actual hardware) are: + * + * (DRP: c = 128MB dual sided, d = 128MB single sided, f = 256MB dual sided) + * + * BUFF_SC TOM DRP DIMM0 DIMM1 + * ---------------------------------------------------------------------------- + * 0x3356 128MB 0x0c 128MB dual-sided - + * 0xcc56 128MB 0xc0 - 128MB dual-sided + * 0x77da 128MB 0x0d 128MB single-sided - + * 0xddda 128MB 0xd0 - 128MB single-sided + * 0x0001 256MB 0xcc 128MB dual-sided 128MB dual-sided + * 0x55c6 256MB 0xdd 128MB single-sided 128MB single-sided + * 0x4445 256MB 0xcd 128MB single-sided 128MB dual-sided + * 0x1145 256MB 0xdc 128MB dual-sided 128MB single-sided + * 0x3356 256MB 0x0f 256MB dual-sided - + * 0xcc56 256MB 0xf0 - 256MB dual-sided + * 0x0001 384MB 0xcf 256MB dual-sided 128MB dual-sided + * 0x0001 384MB 0xfc 128MB dual-sided 256MB dual-sided + * 0x1145 384MB 0xdf 256MB dual-sided 128MB single-sided + * 0x4445 384MB 0xfd 128MB single-sided 256MB dual-sided + * 0x0001 512MB 0xff 256MB dual-sided 256MB dual-sided + */ static void set_dram_buffer_strength(const struct mem_controller *ctrl) { - /* TODO: This needs to be set according to the DRAM tech - * (x8, x16, or x32). Argh, Intel provides no docs on this! - * Currently, it needs to be pulled from the output of - * lspci -xxx Rx92 - */ pci_write_config16(ctrl->d0, BUFF_SC, 0x77da); } -- cgit v1.2.3