X-Git-Url: http://wien.tomnetworks.com/gitweb/?a=blobdiff_plain;f=src%2Fnorthbridge%2Fintel%2Fe7501%2Framinit.c;h=c049d9e5b369336a520cd7195e757f95983a1cd6;hb=b69cb5a31058c0295f2d810c852cc5b52d77225c;hp=ac3bd418662a4856f3ab929f4d6ff11cb8000c54;hpb=b907d321a5d0957f5cbb03d8f9c8d0ff0c23523b;p=coreboot.git diff --git a/src/northbridge/intel/e7501/raminit.c b/src/northbridge/intel/e7501/raminit.c index ac3bd4186..c049d9e5b 100644 --- a/src/northbridge/intel/e7501/raminit.c +++ b/src/northbridge/intel/e7501/raminit.c @@ -17,6 +17,10 @@ #include #include "e7501.h" +/*----------------------------------------------------------------------------- +Definitions: +-----------------------------------------------------------------------------*/ + // Uncomment this to enable run-time checking of DIMM parameters // for dual-channel operation // Unfortunately the code seems to chew up several K of space. @@ -47,10 +51,6 @@ struct dimm_size { unsigned long side2; }; -/*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^*/ -/* DEFINITIONS */ -/**********************************************************************************/ - static const uint32_t refresh_frequency[] = { /* Relative frequency (array value) of each E7501 Refresh Mode Select * (RMS) value (array index) @@ -451,9 +451,10 @@ static const uint32_t maybe_pull_updown_offset_table[] = { 0x88888888, 0x88888888, 0x88888888, 0x88888888, }; -/*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^*/ -/* TABLES */ -/**********************************************************************************/ +/*----------------------------------------------------------------------------- +Delay functions: +-----------------------------------------------------------------------------*/ + #define SLOW_DOWN_IO inb(0x80) //#define SLOW_DOWN_IO udelay(40); @@ -477,27 +478,26 @@ static void do_delay(void) #define EXTRA_DELAY DO_DELAY -/*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^*/ -/* DELAY FUNCTIONS */ -/**********************************************************************************/ - static void die_on_spd_error(int spd_return_value) { if (spd_return_value < 0) die("Error reading SPD info\n"); } -//---------------------------------------------------------------------------------- -// Function: sdram_spd_get_page_size -// Parameters: dimm_socket_address - SMBus address of DIMM socket to interrogate -// Return Value: struct dimm_size - log2(page size) for each side of the DIMM. -// Description: Calculate the page size for each physical bank of the DIMM: -// log2(page size) = (# columns) + log2(data width) -// -// NOTE: page size is the total number of data bits in a row. -// -static struct dimm_size sdram_spd_get_page_size(uint16_t - dimm_socket_address) +/*----------------------------------------------------------------------------- +Serial presence detect (SPD) functions: +-----------------------------------------------------------------------------*/ + +/** + * Calculate the page size for each physical bank of the DIMM: + * log2(page size) = (# columns) + log2(data width) + * + * NOTE: Page size is the total number of data bits in a row. + * + * @param dimm_socket_address SMBus address of DIMM socket to interrogate. + * @return log2(page size) for each side of the DIMM. + */ +static struct dimm_size sdram_spd_get_page_size(uint16_t dimm_socket_address) { uint16_t module_data_width; int value; @@ -554,13 +554,12 @@ static struct dimm_size sdram_spd_get_page_size(uint16_t return pgsz; // Never reached } -//---------------------------------------------------------------------------------- -// Function: sdram_spd_get_width -// Parameters: dimm_socket_address - SMBus address of DIMM socket to interrogate -// Return Value: dimm_size - width in bits of each DIMM side's DRAMs. -// Description: Read the width in bits of each DIMM side's DRAMs via SPD. -// (i.e. 4, 8, 16) -// +/** + * Read the width in bits of each DIMM side's DRAMs via SPD (i.e. 4, 8, 16). + * + * @param dimm_socket_address SMBus address of DIMM socket to interrogate. + * @return Width in bits of each DIMM side's DRAMs. + */ static struct dimm_size sdram_spd_get_width(uint16_t dimm_socket_address) { int value; @@ -601,18 +600,19 @@ static struct dimm_size sdram_spd_get_width(uint16_t dimm_socket_address) return width; } -//---------------------------------------------------------------------------------- -// Function: spd_get_dimm_size -// Parameters: dimm_socket_address - SMBus address of DIMM socket to interrogate -// Return Value: dimm_size - log2(number of bits) for each side of the DIMM -// Description: Calculate the log base 2 size in bits of both DIMM sides. -// log2(# bits) = (# columns) + log2(data width) + -// (# rows) + log2(banks per SDRAM) -// -// Note that it might be easier to use SPD byte 31 here, it has the -// DIMM size as a multiple of 4MB. The way we do it now we can size -// both sides of an asymmetric dimm. -// +/** + * Calculate the log base 2 size in bits of both DIMM sides. + * + * log2(# bits) = (# columns) + log2(data width) + + * (# rows) + log2(banks per SDRAM) + * + * Note that it might be easier to use SPD byte 31 here, it has the DIMM size + * as a multiple of 4MB. The way we do it now we can size both sides of an + * asymmetric DIMM. + * + * @param dimm_socket_address SMBus address of DIMM socket to interrogate. + * @return log2(number of bits) for each side of the DIMM. + */ static struct dimm_size spd_get_dimm_size(unsigned dimm_socket_address) { int value; @@ -651,20 +651,21 @@ static struct dimm_size spd_get_dimm_size(unsigned dimm_socket_address) } #ifdef VALIDATE_DIMM_COMPATIBILITY -//---------------------------------------------------------------------------------- -// Function: are_spd_values_equal -// Parameters: spd_byte_number - -// dimmN_address - SMBus addresses of DIMM sockets to interrogate -// Return Value: 1 if both DIMM sockets report the same value for the specified -// SPD parameter; 0 if the values differed or an error occurred. -// Description: Determine whether two DIMMs have the same value for a SPD parameter. -// + +/** + * Determine whether two DIMMs have the same value for an SPD parameter. + * + * @param spd_byte_number The SPD byte number to compare in both DIMMs. + * @param dimm0_address SMBus address of the 1st DIMM socket to interrogate. + * @param dimm1_address SMBus address of the 2nd DIMM socket to interrogate. + * @return 1 if both DIMM sockets report the same value for the specified + * SPD parameter, 0 if the values differed or an error occurred. + */ static uint8_t are_spd_values_equal(uint8_t spd_byte_number, uint16_t dimm0_address, uint16_t dimm1_address) { uint8_t bEqual = 0; - int dimm0_value = spd_read_byte(dimm0_address, spd_byte_number); int dimm1_value = spd_read_byte(dimm1_address, spd_byte_number); @@ -676,23 +677,24 @@ static uint8_t are_spd_values_equal(uint8_t spd_byte_number, } #endif -//---------------------------------------------------------------------------------- -// Function: spd_get_supported_dimms -// Parameters: ctrl - PCI addresses of memory controller functions, and -// SMBus addresses of DIMM slots on the mainboard -// Return Value: uint8_t - a bitmask indicating which of the possible sockets -// for each channel was found to contain a compatible DIMM. -// Bit 0 corresponds to the closest socket for channel 0, -// Bit 1 to the next socket for channel 0, -// ... -// Bit MAX_DIMM_SOCKETS_PER_CHANNEL-1 to the last socket for channel 0, -// Bit MAX_DIMM_SOCKETS_PER_CHANNEL is the closest socket for channel 1, -// ... -// Bit 2*MAX_DIMM_SOCKETS_PER_CHANNEL-1 is the last socket for channel 1 -// Description: Scan for compatible DIMMs. -// The code in this module only supports dual-channel operation, -// so we test that compatible DIMMs are paired. -// +/** + * Scan for compatible DIMMs. + * + * The code in this module only supports dual-channel operation, so we test + * that compatible DIMMs are paired. + * + * @param ctrl PCI addresses of memory controller functions, and SMBus + * addresses of DIMM slots on the mainboard. + * @return A bitmask indicating which of the possible sockets for each channel + * was found to contain a compatible DIMM. + * Bit 0 corresponds to the closest socket for channel 0 + * Bit 1 to the next socket for channel 0 + * ... + * Bit MAX_DIMM_SOCKETS_PER_CHANNEL-1 to the last socket for channel 0 + * Bit MAX_DIMM_SOCKETS_PER_CHANNEL is the closest socket for channel 1 + * ... + * Bit 2*MAX_DIMM_SOCKETS_PER_CHANNEL-1 is the last socket for channel 1 + */ static uint8_t spd_get_supported_dimms(const struct mem_controller *ctrl) { int i; @@ -828,25 +830,17 @@ static uint8_t spd_get_supported_dimms(const struct mem_controller *ctrl) return dimm_mask; } -/*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^*/ -/* SPD (SERIAL PRESENCE DETECT) FUNCTIONS */ -/**********************************************************************************/ - -//---------------------------------------------------------------------------------- -// Function: do_ram_command -// Parameters: -// command - specifies the command to be sent to the DIMMs: -// RAM_COMMAND_NOP - No Operation -// RAM_COMMAND_PRECHARGE - Precharge all banks -// RAM_COMMAND_MRS - Load Mode Register -// RAM_COMMAND_EMRS - Load Extended Mode Register -// RAM_COMMAND_CBR - Auto Refresh ("CAS-before-RAS") -// RAM_COMMAND_NORMAL - Normal operation -// jedec_mode_bits - for mode register set & extended mode register set -// commands, bits 0-12 contain the register value in JEDEC format. -// Return Value: None -// Description: Send the specified command to all DIMMs. -// +/*----------------------------------------------------------------------------- +SDRAM configuration functions: +-----------------------------------------------------------------------------*/ + +/** + * Send the specified command to all DIMMs. + * + * @param command Specifies the command to be sent to the DIMMs. + * @param jedec_mode_bits For the MRS & EMRS commands, bits 0-12 contain the + * register value in JEDEC format. + */ static void do_ram_command(uint8_t command, uint16_t jedec_mode_bits) { int i; @@ -916,14 +910,15 @@ static void do_ram_command(uint8_t command, uint16_t jedec_mode_bits) } } -//---------------------------------------------------------------------------------- -// Function: set_ram_mode -// Parameters: jedec_mode_bits - for mode register set & extended mode register set -// commands, bits 0-12 contain the register value in JEDEC format. -// Return Value: None -// Description: Set the mode register of all DIMMs. The proper CAS# latency -// setting is added to the mode bits specified by the caller. -// +/** + * Set the mode register of all DIMMs. + * + * The proper CAS# latency setting is added to the mode bits specified + * by the caller. + * + * @param jedec_mode_bits For the MRS & EMRS commands, bits 0-12 contain the + * register value in JEDEC format. + */ static void set_ram_mode(uint16_t jedec_mode_bits) { ASSERT(!(jedec_mode_bits & SDRAM_CAS_MASK)); @@ -948,22 +943,22 @@ static void set_ram_mode(uint16_t jedec_mode_bits) do_ram_command(RAM_COMMAND_MRS, jedec_mode_bits); } -/*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^*/ -/* SDRAM CONFIGURATION FUNCTIONS */ -/**********************************************************************************/ - -//---------------------------------------------------------------------------------- -// Function: configure_dimm_row_boundaries -// Parameters: -// dimm_log2_num_bits - log2(number of bits) for each side of the DIMM -// total_dram_64M_multiple - total DRAM in the system (as a -// multiple of 64 MB) for DIMMs < dimm_index -// dimm_index - which DIMM pair is being processed -// (0..MAX_DIMM_SOCKETS_PER_CHANNEL) -// Return Value: New multiple of 64 MB total DRAM in the system -// Description: Configure the E7501's DRAM Row Boundary registers for the memory -// present in the specified DIMM. -// +/*----------------------------------------------------------------------------- +DIMM-independant configuration functions: +-----------------------------------------------------------------------------*/ + +/** + * Configure the E7501's DRAM Row Boundary (DRB) registers for the memory + * present in the specified DIMM. + * + * @param dimm_log2_num_bits Specifies log2(number of bits) for each side of + * the DIMM. + * @param total_dram_64M_multiple Total DRAM in the system (as a multiple of + * 64 MB) for DIMMs < dimm_index. + * @param dimm_index Which DIMM pair is being processed + * (0..MAX_DIMM_SOCKETS_PER_CHANNEL). + * @return New multiple of 64 MB total DRAM in the system. + */ static uint8_t configure_dimm_row_boundaries(struct dimm_size dimm_log2_num_bits, uint8_t total_dram_64M_multiple, unsigned dimm_index) { int i; @@ -1017,18 +1012,16 @@ static uint8_t configure_dimm_row_boundaries(struct dimm_size dimm_log2_num_bits return total_dram_64M_multiple; } -//---------------------------------------------------------------------------------- -// Function: configure_e7501_ram_addresses -// Parameters: ctrl - PCI addresses of memory controller functions, and -// SMBus addresses of DIMM slots on the mainboard -// dimm_mask - bitmask of populated DIMMs on the board - see -// spd_get_supported_dimms() -// Return Value: None -// Description: Program the E7501's DRAM row boundary addresses and its Top Of -// Low Memory (TOLM). If necessary, set up a remap window so we -// don't waste DRAM that ordinarily would lie behind addresses -// reserved for memory-mapped I/O. -// +/** + * Set the E7501's DRAM row boundary addresses & its Top Of Low Memory (TOLM). + * + * If necessary, set up a remap window so we don't waste DRAM that ordinarily + * would lie behind addresses reserved for memory-mapped I/O. + * + * @param ctrl PCI addresses of memory controller functions, and SMBus + * addresses of DIMM slots on the mainboard. + * @param dimm_mask Bitmask of populated DIMMs, see spd_get_supported_dimms(). + */ static void configure_e7501_ram_addresses(const struct mem_controller *ctrl, uint8_t dimm_mask) { @@ -1130,13 +1123,10 @@ static void configure_e7501_ram_addresses(const struct mem_controller } } -//---------------------------------------------------------------------------------- -// Function: initialize_ecc -// Parameters: None -// Return Value: None -// Description: If we're configured to use ECC, initialize the SDRAM and -// clear the E7501's ECC error flags. -// +/** + * If we're configured to use ECC, initialize the SDRAM and clear the E7501's + * ECC error flags. + */ static void initialize_ecc(void) { uint32_t dram_controller_mode; @@ -1177,17 +1167,15 @@ static void initialize_ecc(void) } -//---------------------------------------------------------------------------------- -// Function: configure_e7501_dram_timing -// Parameters: ctrl - PCI addresses of memory controller functions, and -// SMBus addresses of DIMM slots on the mainboard -// dimm_mask - bitmask of populated DIMMs on the board - see -// spd_get_supported_dimms() -// Return Value: None -// Description: Program the DRAM Timing register of the E7501 (except for CAS# -// latency, which is assumed to have been programmed already), based -// on the parameters of the various installed DIMMs. -// +/** + * Program the DRAM Timing register (DRT) of the E7501 (except for CAS# + * latency, which is assumed to have been programmed already), based on the + * parameters of the various installed DIMMs. + * + * @param ctrl PCI addresses of memory controller functions, and SMBus + * addresses of DIMM slots on the mainboard. + * @param dimm_mask Bitmask of populated DIMMs, see spd_get_supported_dimms(). + */ static void configure_e7501_dram_timing(const struct mem_controller *ctrl, uint8_t dimm_mask) { @@ -1314,16 +1302,14 @@ static void configure_e7501_dram_timing(const struct mem_controller *ctrl, die(SPD_ERROR); } -//---------------------------------------------------------------------------------- -// Function: configure_e7501_cas_latency -// Parameters: ctrl - PCI addresses of memory controller functions, and -// SMBus addresses of DIMM slots on the mainboard -// dimm_mask - bitmask of populated DIMMs on the board - see -// spd_get_supported_dimms() -// Return Value: None -// Description: Determine the shortest CAS# latency that the E7501 and all DIMMs -// have in common, and program the E7501 to use it. -// +/** + * Determine the shortest CAS# latency that the E7501 and all DIMMs have in + * common, and program the E7501 to use it. + * + * @param ctrl PCI addresses of memory controller functions, and SMBus + * addresses of DIMM slots on the mainboard. + * @param dimm_mask Bitmask of populated DIMMs, spd_get_supported_dimms(). + */ static void configure_e7501_cas_latency(const struct mem_controller *ctrl, uint8_t dimm_mask) { @@ -1471,17 +1457,15 @@ static void configure_e7501_cas_latency(const struct mem_controller *ctrl, die(SPD_ERROR); } -//---------------------------------------------------------------------------------- -// Function: configure_e7501_dram_controller_mode -// Parameters: ctrl - PCI addresses of memory controller functions, and -// SMBus addresses of DIMM slots on the mainboard -// dimm_mask - bitmask of populated DIMMs on the board - see -// spd_get_supported_dimms() -// Return Value: None -// Description: Configure the refresh interval so that we refresh no more often -// than required by the "most needy" DIMM. Also disable ECC if any -// of the DIMMs don't support it. -// +/** + * Configure the refresh interval so that we refresh no more often than + * required by the "most needy" DIMM. Also disable ECC if any of the DIMMs + * don't support it. + * + * @param ctrl PCI addresses of memory controller functions, and SMBus + * addresses of DIMM slots on the mainboard. + * @param dimm_mask Bitmask of populated DIMMs, spd_get_supported_dimms(). + */ static void configure_e7501_dram_controller_mode(const struct mem_controller *ctrl, uint8_t dimm_mask) @@ -1579,18 +1563,16 @@ static void configure_e7501_dram_controller_mode(const struct pci_write_config32(PCI_DEV(0, 0, 0), DRC, controller_mode); } -//---------------------------------------------------------------------------------- -// Function: configure_e7501_row_attributes -// Parameters: ctrl - PCI addresses of memory controller functions, and -// SMBus addresses of DIMM slots on the mainboard -// dimm_mask - bitmask of populated DIMMs on the board - see -// spd_get_supported_dimms() -// Return Value: None -// Description: Configure the E7501's DRAM Row Attributes (DRA) registers -// based on DIMM parameters read via SPD. This tells the controller -// the width of the SDRAM chips on each DIMM side (x4 or x8) and -// the page size of each DIMM side (4, 8, 16, or 32 KB). -// +/** + * Configure the E7501's DRAM Row Attributes (DRA) registers based on DIMM + * parameters read via SPD. This tells the controller the width of the SDRAM + * chips on each DIMM side (x4 or x8) and the page size of each DIMM side + * (4, 8, 16, or 32 KB). + * + * @param ctrl PCI addresses of memory controller functions, and SMBus + * addresses of DIMM slots on the mainboard. + * @param dimm_mask Bitmask of populated DIMMs, spd_get_supported_dimms(). + */ static void configure_e7501_row_attributes(const struct mem_controller *ctrl, uint8_t dimm_mask) { @@ -1634,14 +1616,12 @@ static void configure_e7501_row_attributes(const struct mem_controller pci_write_config32(PCI_DEV(0, 0, 0), DRA, row_attributes); } -//---------------------------------------------------------------------------------- -// Function: enable_e7501_clocks -// Parameters: dimm_mask - bitmask of populated DIMMs on the board - see -// spd_get_supported_dimms() -// Return Value: None -// Description: Enable clock signals for populated DIMM sockets and disable them -// for unpopulated sockets (to reduce EMI). -// +/* + * Enable clock signals for populated DIMM sockets and disable them for + * unpopulated sockets (to reduce EMI). + * + * @param dimm_mask Bitmask of populated DIMMs, see spd_get_supported_dimms(). + */ static void enable_e7501_clocks(uint8_t dimm_mask) { int i; @@ -1660,17 +1640,11 @@ static void enable_e7501_clocks(uint8_t dimm_mask) pci_write_config8(PCI_DEV(0, 0, 0), CKDIS, clock_disable); } -/*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^*/ -/* DIMM-DEDEPENDENT CONFIGURATION FUNCTIONS */ -/**********************************************************************************/ - -//---------------------------------------------------------------------------------- -// Function: RAM_RESET_DDR_PTR -// Parameters: ctrl - PCI addresses of memory controller functions, and -// SMBus addresses of DIMM slots on the mainboard -// Return Value: None -// Description: DDR Receive FIFO RE-Sync (?) -// +/* DIMM-dedependent configuration functions */ + +/** + * DDR Receive FIFO RE-Sync (?) + */ static void RAM_RESET_DDR_PTR(void) { uint8_t byte; @@ -1683,17 +1657,15 @@ static void RAM_RESET_DDR_PTR(void) pci_write_config8(PCI_DEV(0, 0, 0), 0x88, byte); } -//---------------------------------------------------------------------------------- -// Function: ram_set_d0f0_regs -// Parameters: None -// Return Value: None -// Description: Set E7501 registers that are either independent of DIMM specifics, -// or establish default settings that will be overridden when we -// learn the specifics. -// This sets PCI configuration registers to known good values based -// on the table 'constant_register_values', which are a triple of -// configuration register offset, mask, and bits to set. -// +/** + * Set E7501 registers that are either independent of DIMM specifics, or + * establish default settings that will be overridden when we learn the + * specifics. + * + * This sets PCI configuration registers to known good values based on the + * table 'constant_register_values', which are a triple of configuration + * register offset, mask, and bits to set. + */ static void ram_set_d0f0_regs(void) { int i; @@ -1726,14 +1698,13 @@ static void ram_set_d0f0_regs(void) } } -//---------------------------------------------------------------------------------- -// Function: write_8dwords -// Parameters: src_addr -// dst_addr -// Return Value: None -// Description: Copy 64 bytes from one location to another. -// -static void write_8dwords(const uint32_t * src_addr, uint32_t dst_addr) +/** + * Copy 64 bytes from one location to another. + * + * @param src_addr TODO + * @param dst_addr TODO + */ +static void write_8dwords(const uint32_t *src_addr, uint32_t dst_addr) { int i; for (i = 0; i < 8; i++) { @@ -1743,17 +1714,16 @@ static void write_8dwords(const uint32_t * src_addr, uint32_t dst_addr) } } -//---------------------------------------------------------------------------------- -// Function: ram_set_rcomp_regs -// Parameters: None -// Return Value: None -// Description: Set the E7501's (undocumented) RCOMP registers. -// Per the 855PM datasheet and IXP2800 HW Initialization Reference -// Manual, RCOMP registers appear to affect drive strength, -// pullup/pulldown offset, and slew rate of various signal groups. -// Comments below are conjecture based on apparent similarity -// between the E7501 and these two chips. -// +/** + * Set the E7501's (undocumented) RCOMP registers. + * + * Per the 855PM datasheet and IXP2800 HW Initialization Reference Manual, + * RCOMP registers appear to affect drive strength, pullup/pulldown offset, + * and slew rate of various signal groups. + * + * Comments below are conjecture based on apparent similarity between the + * E7501 and these two chips. + */ static void ram_set_rcomp_regs(void) { uint32_t dword; @@ -1857,20 +1827,19 @@ static void ram_set_rcomp_regs(void) } -/*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^*/ -/* DIMM-INDEPENDENT CONFIGURATION FUNCTIONS */ -/**********************************************************************************/ - -//---------------------------------------------------------------------------------- -// Function: sdram_enable -// Parameters: controllers - not used -// ctrl - PCI addresses of memory controller functions, and -// SMBus addresses of DIMM slots on the mainboard -// Return Value: None -// Description: Go through the JEDEC initialization sequence for all DIMMs, -// then enable refresh and initialize ECC and memory to zero. -// Upon exit, SDRAM is up and running. -// +/*----------------------------------------------------------------------------- +Public interface: +-----------------------------------------------------------------------------*/ + +/** + * Go through the JEDEC initialization sequence for all DIMMs, then enable + * refresh and initialize ECC and memory to zero. Upon exit, SDRAM is up + * and running. + * + * @param controllers Not used. + * @param ctrl PCI addresses of memory controller functions, and SMBus + * addresses of DIMM slots on the mainboard. + */ static void sdram_enable(int controllers, const struct mem_controller *ctrl) { @@ -1975,16 +1944,14 @@ static void sdram_enable(int controllers, DUMPNORTH(); } -//---------------------------------------------------------------------------------- -// Function: sdram_set_spd_registers -// Parameters: ctrl - PCI addresses of memory controller functions, and -// SMBus addresses of DIMM slots on the mainboard -// Return Value: None -// Description: Configure SDRAM controller parameters that depend on -// characteristics of the DIMMs installed in the system. These -// characteristics are read from the DIMMs via the standard Serial -// Presence Detect (SPD) interface. -// +/** + * Configure SDRAM controller parameters that depend on characteristics of the + * DIMMs installed in the system. These characteristics are read from the + * DIMMs via the standard Serial Presence Detect (SPD) interface. + * + * @param ctrl PCI addresses of memory controller functions, and SMBus + * addresses of DIMM slots on the mainboard. + */ static void sdram_set_spd_registers(const struct mem_controller *ctrl) { uint8_t dimm_mask; @@ -2023,14 +1990,13 @@ static void sdram_set_spd_registers(const struct mem_controller *ctrl) pci_write_config16(PCI_DEV(0, 0, 0), SKPD, dimm_mask); } -//---------------------------------------------------------------------------------- -// Function: sdram_set_registers -// Parameters: ctrl - PCI addresses of memory controller functions, and -// SMBus addresses of DIMM slots on the mainboard -// Return Value: None -// Description: Do basic ram setup that does NOT depend on serial presence detect -// information (i.e. independent of DIMM specifics). -// +/** + * Do basic RAM setup that does NOT depend on serial presence detect + * information (i.e. independent of DIMM specifics). + * + * @param ctrl PCI addresses of memory controller functions, and SMBus + * addresses of DIMM slots on the mainboard. + */ static void sdram_set_registers(const struct mem_controller *ctrl) { RAM_DEBUG_MESSAGE("Northbridge prior to SDRAM init:\n"); @@ -2039,7 +2005,3 @@ static void sdram_set_registers(const struct mem_controller *ctrl) ram_set_rcomp_regs(); ram_set_d0f0_regs(); } - -/*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^*/ -/* PUBLIC INTERFACE */ -/**********************************************************************************/