summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/ddr-8xxx/ddr3_dimm_params.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/powerpc/ddr-8xxx/ddr3_dimm_params.c')
-rw-r--r--arch/powerpc/ddr-8xxx/ddr3_dimm_params.c193
1 files changed, 193 insertions, 0 deletions
diff --git a/arch/powerpc/ddr-8xxx/ddr3_dimm_params.c b/arch/powerpc/ddr-8xxx/ddr3_dimm_params.c
new file mode 100644
index 0000000000..4f44925ab9
--- /dev/null
+++ b/arch/powerpc/ddr-8xxx/ddr3_dimm_params.c
@@ -0,0 +1,193 @@
+/*
+ * Copyright 2008-2012 Freescale Semiconductor, Inc.
+ * Dave Liu <daveliu@freescale.com>
+ *
+ * calculate the organization and timing parameter
+ * from ddr3 spd, please refer to the spec
+ * JEDEC standard No.21-C 4_01_02_11R18.pdf
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * Version 2 as published by the Free Software Foundation.
+ */
+
+#include <common.h>
+#include <asm/fsl_ddr_sdram.h>
+#include "ddr.h"
+
+/*
+ * Calculate the Density of each Physical Rank.
+ * Returned size is in bytes.
+ *
+ * each rank size =
+ * sdram capacity(bit) / 8 * primary bus width / sdram width
+ *
+ * where: sdram capacity = spd byte4[3:0]
+ * primary bus width = spd byte8[2:0]
+ * sdram width = spd byte7[2:0]
+ *
+ * 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
+ *
+ * SPD byte8 - module memory bus width
+ * bit[2:0] primary bus width
+ * 000 8bits
+ * 001 16bits
+ * 010 32bits
+ * 011 64bits
+ *
+ * SPD byte7 - module organiztion
+ * bit[2:0] sdram device width
+ * 000 4bits
+ * 001 8bits
+ * 010 16bits
+ * 011 32bits
+ */
+static uint64_t compute_ranksize(const struct ddr3_spd_eeprom *spd)
+{
+ uint64_t bsize;
+ int sdram_cap_bsize = 0, prim_bus_width = 0, sdram_width = 0;
+
+ if ((spd->density_banks & 0xf) < 7)
+ sdram_cap_bsize = (spd->density_banks & 0xf) + 28;
+ if ((spd->bus_width & 0x7) < 4)
+ prim_bus_width = (spd->bus_width & 0x7) + 3;
+ if ((spd->organization & 0x7) < 4)
+ sdram_width = (spd->organization & 0x7) + 2;
+
+ bsize = 1ULL << (sdram_cap_bsize - 3 + prim_bus_width - sdram_width);
+
+ return bsize;
+}
+
+/*
+ * compute_dimm_parameters for DDR3 SPD
+ *
+ * Compute DIMM parameters based upon the SPD information in spd.
+ * Writes the results to the dimm_params_s structure pointed by pdimm.
+ *
+ */
+uint32_t
+compute_dimm_parameters(const generic_spd_eeprom_t *spdin,
+ struct dimm_params_s *pdimm)
+{
+ const struct ddr3_spd_eeprom *spd = spdin;
+ uint32_t mtb_ps;
+ int retval, ftb_tmp;
+
+ if (spd->mem_type != SPD_MEMTYPE_DDR3)
+ goto error;
+
+ retval = ddr3_spd_check(spd);
+ if (retval)
+ goto error;
+
+ memset(pdimm->mpart, 0, sizeof(pdimm->mpart));
+ if ((spd->info_size_crc & 0xf) > 1)
+ 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->data_width = pdimm->primary_sdram_width + pdimm->ec_sdram_width;
+ 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->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_UDIMM:
+ /* Unbuffered DIMMs */
+ if (spd->mod_section.unbuffered.addr_mapping & 0x1)
+ pdimm->mirrored_dimm = 1;
+ break;
+
+ default:
+ goto error;
+ }
+
+ /* SDRAM device parameters */
+ pdimm->n_row_addr = ((spd->addressing >> 3) & 0x7) + 12;
+ pdimm->n_col_addr = (spd->addressing & 0x7) + 9;
+ pdimm->n_banks_per_sdram_device =
+ 8 << ((spd->density_banks >> 4) & 0x7);
+
+ /*
+ * The SPD spec does not define an ECC bit. The DIMM is considered
+ * to have ECC capability if the extension bus exists.
+ */
+ if (pdimm->ec_sdram_width)
+ pdimm->edc_config = 0x02;
+ else
+ pdimm->edc_config = 0x00;
+
+ /*
+ * The SPD spec does not define the burst length byte.
+ * but the DDR3 spec defines BL8 and BC4, on bit 3 and
+ * bit 2.
+ */
+ pdimm->burst_lengths_bitmask = 0x0c;
+ pdimm->row_density = __ilog2(pdimm->rank_density);
+
+ mtb_ps = (spd->mtb_dividend * 1000) / spd->mtb_divisor;
+ pdimm->mtb_ps = mtb_ps;
+
+ ftb_tmp = spd->ftb_div & 0xf0;
+ pdimm->ftb_10th_ps = ((ftb_tmp >> 4) * 10) / ftb_tmp;
+
+ pdimm->tCKmin_X_ps = spd->tck_min * mtb_ps +
+ (spd->fine_tck_min * ftb_tmp) / 10;
+ pdimm->caslat_X = ((spd->caslat_msb << 8) | spd->caslat_lsb) << 4;
+
+ pdimm->taa_ps = spd->taa_min * mtb_ps +
+ (spd->fine_taa_min * ftb_tmp) / 10;
+
+ pdimm->tRCD_ps = spd->trcd_min * mtb_ps +
+ (spd->fine_trcd_min * ftb_tmp) / 10;
+
+ pdimm->tRP_ps = spd->trp_min * mtb_ps +
+ (spd->fine_trp_min * ftb_tmp) / 10;
+ pdimm->tRAS_ps = (((spd->tras_trc_ext & 0xf) << 8) | spd->tras_min_lsb)
+ * mtb_ps;
+ pdimm->tWR_ps = spd->twr_min * mtb_ps;
+ pdimm->tWTR_ps = spd->twtr_min * mtb_ps;
+ pdimm->tRFC_ps = ((spd->trfc_min_msb << 8) | spd->trfc_min_lsb)
+ * mtb_ps;
+ pdimm->tRRD_ps = spd->trrd_min * mtb_ps;
+ pdimm->tRC_ps = (((spd->tras_trc_ext & 0xf0) << 4) | spd->trc_min_lsb);
+ pdimm->tRC_ps *= mtb_ps;
+ pdimm->tRC_ps += (spd->fine_trc_min * ftb_tmp) / 10;
+
+ pdimm->tRTP_ps = spd->trtp_min * mtb_ps;
+
+ /*
+ * Average periodic refresh interval
+ * tREFI = 7.8 us at normal temperature range
+ * = 3.9 us at ext temperature range
+ */
+ pdimm->refresh_rate_ps = 7800000;
+ if ((spd->therm_ref_opt & 0x1) && !(spd->therm_ref_opt & 0x2)) {
+ pdimm->refresh_rate_ps = 3900000;
+ pdimm->extended_op_srt = 1;
+ }
+
+ pdimm->tfaw_ps = (((spd->tfaw_msb & 0xf) << 8) | spd->tfaw_min)
+ * mtb_ps;
+
+ return 0;
+error:
+ return 1;
+}