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path: root/drivers/ddr/fsl/ddr4_dimm_params.c
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Diffstat (limited to 'drivers/ddr/fsl/ddr4_dimm_params.c')
-rw-r--r--drivers/ddr/fsl/ddr4_dimm_params.c300
1 files changed, 300 insertions, 0 deletions
diff --git a/drivers/ddr/fsl/ddr4_dimm_params.c b/drivers/ddr/fsl/ddr4_dimm_params.c
new file mode 100644
index 0000000..4745b7f
--- /dev/null
+++ b/drivers/ddr/fsl/ddr4_dimm_params.c
@@ -0,0 +1,300 @@
+/*
+ * Copyright 2014 Freescale Semiconductor, Inc.
+ *
+ * calculate the organization and timing parameter
+ * from ddr3 spd, please refer to the spec
+ * JEDEC standard No.21-C 4_01_02_12R23A.pdf
+ *
+ *
+ */
+
+#include <common.h>
+#include <fsl_ddr_sdram.h>
+
+#include <fsl_ddr.h>
+
+/*
+ * Calculate the Density of each Physical Rank.
+ * Returned size is in bytes.
+ *
+ * Total DIMM size =
+ * sdram capacity(bit) / 8 * primary bus width / sdram width
+ * * Logical Ranks per DIMM
+ *
+ * where: sdram capacity = spd byte4[3:0]
+ * primary bus width = spd byte13[2:0]
+ * sdram width = spd byte12[2:0]
+ * Logical Ranks per DIMM = spd byte12[5:3] for SDP, DDP, QDP
+ * spd byte12{5:3] * spd byte6[6:4] for 3DS
+ *
+ * To simplify each rank size = total DIMM size / Number of Package Ranks
+ * where Number of Package Ranks = spd byte12[5:3]
+ *
+ * SPD byte4 - sdram density and banks
+ * bit[3:0] size(bit) size(byte)
+ * 0000 256Mb 32MB
+ * 0001 512Mb 64MB
+ * 0010 1Gb 128MB
+ * 0011 2Gb 256MB
+ * 0100 4Gb 512MB
+ * 0101 8Gb 1GB
+ * 0110 16Gb 2GB
+ * 0111 32Gb 4GB
+ *
+ * SPD byte13 - module memory bus width
+ * bit[2:0] primary bus width
+ * 000 8bits
+ * 001 16bits
+ * 010 32bits
+ * 011 64bits
+ *
+ * SPD byte12 - module organization
+ * bit[2:0] sdram device width
+ * 000 4bits
+ * 001 8bits
+ * 010 16bits
+ * 011 32bits
+ *
+ * SPD byte12 - module organization
+ * bit[5:3] number of package ranks per DIMM
+ * 000 1
+ * 001 2
+ * 010 3
+ * 011 4
+ *
+ * SPD byte6 - SDRAM package type
+ * bit[6:4] Die count
+ * 000 1
+ * 001 2
+ * 010 3
+ * 011 4
+ * 100 5
+ * 101 6
+ * 110 7
+ * 111 8
+ *
+ * SPD byte6 - SRAM package type
+ * bit[1:0] Signal loading
+ * 00 Not specified
+ * 01 Multi load stack
+ * 10 Sigle load stack (3DS)
+ * 11 Reserved
+ */
+static unsigned long long
+compute_ranksize(const struct ddr4_spd_eeprom_s *spd)
+{
+ unsigned long long bsize;
+
+ int nbit_sdram_cap_bsize = 0;
+ int nbit_primary_bus_width = 0;
+ int nbit_sdram_width = 0;
+ int die_count = 0;
+ bool package_3ds;
+
+ if ((spd->density_banks & 0xf) <= 7)
+ nbit_sdram_cap_bsize = (spd->density_banks & 0xf) + 28;
+ if ((spd->bus_width & 0x7) < 4)
+ nbit_primary_bus_width = (spd->bus_width & 0x7) + 3;
+ if ((spd->organization & 0x7) < 4)
+ nbit_sdram_width = (spd->organization & 0x7) + 2;
+ package_3ds = (spd->package_type & 0x3) == 0x2;
+ if (package_3ds)
+ die_count = (spd->package_type >> 4) & 0x7;
+
+ bsize = 1ULL << (nbit_sdram_cap_bsize - 3 +
+ nbit_primary_bus_width - nbit_sdram_width +
+ die_count);
+
+ debug("DDR: DDR III rank density = 0x%16llx\n", bsize);
+
+ return bsize;
+}
+
+#define spd_to_ps(mtb, ftb) \
+ (mtb * pdimm->mtb_ps + (ftb * pdimm->ftb_10th_ps) / 10)
+/*
+ * ddr_compute_dimm_parameters for DDR3 SPD
+ *
+ * Compute DIMM parameters based upon the SPD information in spd.
+ * Writes the results to the dimm_params_t structure pointed by pdimm.
+ *
+ */
+unsigned int
+ddr_compute_dimm_parameters(const generic_spd_eeprom_t *spd,
+ dimm_params_t *pdimm,
+ unsigned int dimm_number)
+{
+ unsigned int retval;
+ int i;
+
+ if (spd->mem_type) {
+ if (spd->mem_type != SPD_MEMTYPE_DDR4) {
+ printf("DIMM %u: is not a DDR4 SPD.\n", dimm_number);
+ return 1;
+ }
+ } else {
+ memset(pdimm, 0, sizeof(dimm_params_t));
+ return 1;
+ }
+
+ retval = ddr4_spd_check(spd);
+ if (retval) {
+ printf("DIMM %u: failed checksum\n", dimm_number);
+ return 2;
+ }
+
+ /*
+ * The part name in ASCII in the SPD EEPROM is not null terminated.
+ * Guarantee null termination here by presetting all bytes to 0
+ * and copying the part name in ASCII from the SPD onto it
+ */
+ memset(pdimm->mpart, 0, sizeof(pdimm->mpart));
+ if ((spd->info_size_crc & 0xF) > 2)
+ memcpy(pdimm->mpart, spd->mpart, sizeof(pdimm->mpart) - 1);
+
+ /* DIMM organization parameters */
+ pdimm->n_ranks = ((spd->organization >> 3) & 0x7) + 1;
+ pdimm->rank_density = compute_ranksize(spd);
+ pdimm->capacity = pdimm->n_ranks * pdimm->rank_density;
+ pdimm->primary_sdram_width = 1 << (3 + (spd->bus_width & 0x7));
+ if ((spd->bus_width >> 3) & 0x3)
+ pdimm->ec_sdram_width = 8;
+ else
+ pdimm->ec_sdram_width = 0;
+ pdimm->data_width = pdimm->primary_sdram_width
+ + pdimm->ec_sdram_width;
+ pdimm->device_width = 1 << ((spd->organization & 0x7) + 2);
+
+ /* These are the types defined by the JEDEC DDR3 SPD spec */
+ pdimm->mirrored_dimm = 0;
+ pdimm->registered_dimm = 0;
+ switch (spd->module_type & DDR3_SPD_MODULETYPE_MASK) {
+ case DDR3_SPD_MODULETYPE_RDIMM:
+ /* Registered/buffered DIMMs */
+ pdimm->registered_dimm = 1;
+ break;
+
+ case DDR3_SPD_MODULETYPE_UDIMM:
+ case DDR3_SPD_MODULETYPE_SO_DIMM:
+ /* Unbuffered DIMMs */
+ if (spd->mod_section.unbuffered.addr_mapping & 0x1)
+ pdimm->mirrored_dimm = 1;
+ break;
+
+ default:
+ printf("unknown module_type 0x%02X\n", spd->module_type);
+ return 1;
+ }
+
+ /* SDRAM device parameters */
+ pdimm->n_row_addr = ((spd->addressing >> 3) & 0x7) + 12;
+ pdimm->n_col_addr = (spd->addressing & 0x7) + 9;
+ pdimm->bank_addr_bits = (spd->density_banks >> 4) & 0x3;
+ pdimm->bank_group_bits = (spd->density_banks >> 6) & 0x3;
+
+ /*
+ * The SPD spec has not the ECC bit,
+ * We consider the DIMM as ECC capability
+ * when the extension bus exist
+ */
+ if (pdimm->ec_sdram_width)
+ pdimm->edc_config = 0x02;
+ else
+ pdimm->edc_config = 0x00;
+
+ /*
+ * The SPD spec has not the burst length byte
+ * but DDR4 spec has nature BL8 and BC4,
+ * BL8 -bit3, BC4 -bit2
+ */
+ pdimm->burst_lengths_bitmask = 0x0c;
+ pdimm->row_density = __ilog2(pdimm->rank_density);
+
+ /* MTB - medium timebase
+ * The MTB in the SPD spec is 125ps,
+ *
+ * FTB - fine timebase
+ * use 1/10th of ps as our unit to avoid floating point
+ * eg, 10 for 1ps, 25 for 2.5ps, 50 for 5ps
+ */
+ if ((spd->timebases & 0xf) == 0x0) {
+ pdimm->mtb_ps = 125;
+ pdimm->ftb_10th_ps = 10;
+
+ } else {
+ printf("Unknown Timebases\n");
+ }
+
+ /* sdram minimum cycle time */
+ pdimm->tckmin_x_ps = spd_to_ps(spd->tck_min, spd->fine_tck_min);
+
+ /* sdram max cycle time */
+ pdimm->tckmax_ps = spd_to_ps(spd->tck_max, spd->fine_tck_max);
+
+ /*
+ * CAS latency supported
+ * bit0 - CL7
+ * bit4 - CL11
+ * bit8 - CL15
+ * bit12- CL19
+ * bit16- CL23
+ */
+ pdimm->caslat_x = (spd->caslat_b1 << 7) |
+ (spd->caslat_b2 << 15) |
+ (spd->caslat_b3 << 23);
+
+ BUG_ON(spd->caslat_b4 != 0);
+
+ /*
+ * min CAS latency time
+ */
+ pdimm->taa_ps = spd_to_ps(spd->taa_min, spd->fine_taa_min);
+
+ /*
+ * min RAS to CAS delay time
+ */
+ pdimm->trcd_ps = spd_to_ps(spd->trcd_min, spd->fine_trcd_min);
+
+ /*
+ * Min Row Precharge Delay Time
+ */
+ pdimm->trp_ps = spd_to_ps(spd->trp_min, spd->fine_trp_min);
+
+ /* min active to precharge delay time */
+ pdimm->tras_ps = (((spd->tras_trc_ext & 0xf) << 8) +
+ spd->tras_min_lsb) * pdimm->mtb_ps;
+
+ /* min active to actice/refresh delay time */
+ pdimm->trc_ps = spd_to_ps((((spd->tras_trc_ext & 0xf0) << 4) +
+ spd->trc_min_lsb), spd->fine_trc_min);
+ /* Min Refresh Recovery Delay Time */
+ pdimm->trfc1_ps = ((spd->trfc1_min_msb << 8) | (spd->trfc1_min_lsb)) *
+ pdimm->mtb_ps;
+ pdimm->trfc2_ps = ((spd->trfc2_min_msb << 8) | (spd->trfc2_min_lsb)) *
+ pdimm->mtb_ps;
+ pdimm->trfc4_ps = ((spd->trfc4_min_msb << 8) | (spd->trfc4_min_lsb)) *
+ pdimm->mtb_ps;
+ /* min four active window delay time */
+ pdimm->tfaw_ps = (((spd->tfaw_msb & 0xf) << 8) | spd->tfaw_min) *
+ pdimm->mtb_ps;
+
+ /* min row active to row active delay time, different bank group */
+ pdimm->trrds_ps = spd_to_ps(spd->trrds_min, spd->fine_trrds_min);
+ /* min row active to row active delay time, same bank group */
+ pdimm->trrdl_ps = spd_to_ps(spd->trrdl_min, spd->fine_trrdl_min);
+ /* min CAS to CAS Delay Time (tCCD_Lmin), same bank group */
+ pdimm->tccdl_ps = spd_to_ps(spd->tccdl_min, spd->fine_tccdl_min);
+
+ /*
+ * Average periodic refresh interval
+ * tREFI = 7.8 us at normal temperature range
+ */
+ pdimm->refresh_rate_ps = 7800000;
+
+ for (i = 0; i < 18; i++)
+ pdimm->dq_mapping[i] = spd->mapping[i];
+
+ pdimm->dq_mapping_ors = ((spd->mapping[0] >> 6) & 0x3) == 0 ? 1 : 0;
+
+ return 0;
+}