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-rw-r--r--src/northbridge/intel/i440bx/raminit.c72
1 files changed, 42 insertions, 30 deletions
diff --git a/src/northbridge/intel/i440bx/raminit.c b/src/northbridge/intel/i440bx/raminit.c
index eceaaee4eb..ebcd368511 100644
--- a/src/northbridge/intel/i440bx/raminit.c
+++ b/src/northbridge/intel/i440bx/raminit.c
@@ -29,15 +29,15 @@
Macros and definitions.
-----------------------------------------------------------------------------*/
+#define NB PCI_DEV(0, 0, 0)
+
/* Debugging macros. */
#if CONFIG_DEBUG_RAM_SETUP
#define PRINT_DEBUG(x) print_debug(x)
#define PRINT_DEBUG_HEX8(x) print_debug_hex8(x)
#define PRINT_DEBUG_HEX16(x) print_debug_hex16(x)
#define PRINT_DEBUG_HEX32(x) print_debug_hex32(x)
-// no dump_pci_device in src/northbridge/intel/i440bx
-// #define DUMPNORTH() dump_pci_device(PCI_DEV(0, 0, 0))
-#define DUMPNORTH()
+#define DUMPNORTH() dump_pci_device(NB)
#else
#define PRINT_DEBUG(x)
#define PRINT_DEBUG_HEX8(x)
@@ -46,8 +46,6 @@ Macros and definitions.
#define DUMPNORTH()
#endif
-#define NB PCI_DEV(0, 0, 0)
-
/* SDRAMC[7:5] - SDRAM Mode Select (SMS). */
#define RAM_COMMAND_NORMAL 0x0
#define RAM_COMMAND_NOP 0x1
@@ -70,7 +68,7 @@ static const uint32_t refresh_rate_map[] = {
};
/* Table format: register, bitmask, value. */
-static const long register_values[] = {
+static const u8 register_values[] = {
/* NBXCFG - NBX Configuration Register
* 0x50 - 0x53
*
@@ -131,9 +129,8 @@ static const long register_values[] = {
* 0 = A7# is sampled asserted (i.e., 0)
* [01:00] Reserved
*/
- // TODO
NBXCFG + 0, 0x00, 0x0c,
- // NBXCFG + 1, 0x00, 0xa0,
+ // TODO: Bit 15 should be 0 for multiprocessor boards
NBXCFG + 1, 0x00, 0x80,
NBXCFG + 2, 0x00, 0x00,
NBXCFG + 3, 0x00, 0xff,
@@ -143,7 +140,12 @@ static const long register_values[] = {
*
* [7:6] Reserved
* [5:5] Module Mode Configuration (MMCONFIG)
- * TODO
+ * The combination of SDRAMPWR and this bit (which is set by an
+ * external strapping option) determine how CKE works.
+ * SDRAMPWR MMCONFIG
+ * 0 0 = 3 DIMM, CKE0[5:0] driven
+ * X 1 = 3 DIMM, CKE0 only
+ * 1 0 = 4 DIMM, GCKE only
* [4:3] DRAM Type (DT)
* 00 = EDO
* 01 = SDRAM
@@ -252,12 +254,25 @@ static const long register_values[] = {
* Sets the row page size for SDRAM. For EDO memory, the page
* size is fixed at 2 KB.
*
- * [15:0] Page Size (PS)
- * TODO
+ * Bits[1:0] Page Size
+ * 00 2 KB
+ * 01 4 KB
+ * 10 8 KB
+ * 11 Reserved
+ *
+ * RPS bits Corresponding DRB register
+ * [01:00] DRB[0], row 0
+ * [03:02] DRB[1], row 1
+ * [05:04] DRB[2], row 2
+ * [07:06] DRB[3], row 3
+ * [09:08] DRB[4], row 4
+ * [11:10] DRB[5], row 5
+ * [13:12] DRB[6], row 6
+ * [15:14] DRB[7], row 7
*/
- // TODO
- RPS + 0, 0x00, 0x00,
- RPS + 1, 0x00, 0x00,
+ /* Power on defaults to 2KB. Will be set later. */
+ // RPS + 0, 0x00, 0x00,
+ // RPS + 1, 0x00, 0x00,
/* SDRAMC - SDRAM Control Register
* 0x76 - 0x77
@@ -266,8 +281,7 @@ static const long register_values[] = {
* [09:08] Idle/Pipeline DRAM Leadoff Timing (IPDLT)
* 00 = Illegal
* 01 = Add a clock delay to the lead-off clock count
- * 10 = Illegal
- * 11 = Illegal
+ * 1x = Illegal
* [07:05] SDRAM Mode Select (SMS)
* 000 = Normal SDRAM Operation (default)
* 001 = NOP Command Enable
@@ -296,7 +310,7 @@ static const long register_values[] = {
#if CONFIG_SDRAMPWR_4DIMM
SDRAMC + 0, 0x00, 0x10, /* The board has 4 DIMM slots. */
#else
- SDRAMC + 0, 0x00, 0x00, /* The board has 3 DIMM slots.*/
+ SDRAMC + 0, 0x00, 0x00, /* The board has 3 DIMM slots. */
#endif
SDRAMC + 1, 0x00, 0x00,
@@ -304,7 +318,9 @@ static const long register_values[] = {
* 0x78 - 0x79
*
* [15:08] Banks per Row (BPR)
- * TODO
+ * Each bit in this field corresponds to one row of the memory
+ * array. Bit 15 corresponds to row 7 while bit 8 corresponds
+ * to row 0. Bits for empty rows are "don't care".
* 0 = 2 banks
* 1 = 4 banks
* [07:05] Reserved
@@ -320,7 +336,6 @@ static const long register_values[] = {
* 0111 = 32 clocks
* 1xxx = Infinite (pages are not closed for idle condition)
*/
- // TODO
PGPOL + 0, 0x00, 0x00,
PGPOL + 1, 0x00, 0xff,
@@ -354,7 +369,6 @@ static const long register_values[] = {
/* Enable normal refresh and the gated clock. */
// TODO: Only do this later?
// PMCR, 0x00, 0x14,
- // PMCR, 0x00, 0x10,
PMCR, 0x00, 0x00,
/* Enable SCRR.SRRAEN and let BX choose the SRR. */
@@ -458,11 +472,11 @@ static void set_dram_buffer_strength(void)
}
}
- /* Algorithm bitmap for programming MBSC[39:0] and MBFS[23:0]
+ /* Algorithm bitmap for programming MBSC[39:0] and MBFS[23:0].
*
- * 440BX datasheet says buffer frequency is independent from bus frequency
- * and mismatch both ways are possible. This is how it is programmed
- * in ASUS P2B-LS.
+ * The 440BX datasheet says buffer frequency is independent from bus
+ * frequency and mismatch both ways are possible. This is how it is
+ * programmed in the ASUS P2B-LS mainboard.
*
* There are four main conditions to check when programming DRAM buffer
* frequency and strength:
@@ -523,7 +537,8 @@ static void set_dram_buffer_strength(void)
* +--------------------------------------- MAA[13:0],WEA#,SRASA#,SCASA#
* MBSC[47:40] and MBFS[23] are reserved.
*
- * This algorithm is checked against P2B-LS factory BIOS. It has 4 DIMM slots.
+ * This algorithm is checked against the ASUS P2B-LS (which has
+ * 4 DIMM slots) factory BIOS.
* Therefore it assumes a board with 4 slots, and will need testing
* on boards with 3 DIMM slots.
*/
@@ -946,17 +961,14 @@ static void sdram_set_spd_registers(void)
/* Setup DRAM row boundary registers and other attributes. */
set_dram_row_attributes();
- /* TODO: Set SDRAMC. */
- pci_write_config16(NB, SDRAMC, 0x0010); /* SDRAMPWR=1: 4 DIMM config */
-
- /* TODO */
+ /* Setup DRAM buffer strength. */
set_dram_buffer_strength();
/* TODO: Set PMCR? */
// pci_write_config8(NB, PMCR, 0x14);
pci_write_config8(NB, PMCR, 0x10);
- /* TODO? */
+ /* TODO: This is for EDO memory only. */
pci_write_config8(NB, DRAMT, 0x03);
}