1 files changed, 246 insertions, 0 deletions
diff --git a/arch/powerpc/ddr-8xxx/main.c b/arch/powerpc/ddr-8xxx/main.c
new file mode 100644
index 0000000000..99b877b5ca
--- /dev/null
+++ b/arch/powerpc/ddr-8xxx/main.c
@@ -0,0 +1,246 @@
+/*
+ * Copyright 2008-2012 Freescale Semiconductor, Inc.
+ *
+ * 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.
+ */
+
+/*
+ * Generic driver for Freescale DDR2 memory controller.
+ * Based on code from spd_sdram.c
+ * Author: James Yang [at freescale.com]
+ */
+
+#include <common.h>
+#include <config.h>
+#include <asm/fsl_law.h>
+#include <asm/fsl_ddr_sdram.h>
+#include "ddr.h"
+
+static int get_spd(generic_spd_eeprom_t *spd,
+		      struct ddr_board_info_s *bi, u8 i2c_address)
+{
+	int ret;
+
+	fsl_i2c_init(bi->i2c_base, bi->i2c_speed, bi->i2c_slave);
+	ret = fsl_i2c_read(bi->i2c_base, i2c_address, 0, 1, (uchar *) spd,
+			sizeof(generic_spd_eeprom_t));
+	fsl_i2c_stop(bi->i2c_base);
+
+	return ret;
+}
+
+int fsl_ddr_get_spd(generic_spd_eeprom_t *ctrl_dimms_spd,
+		struct ddr_board_info_s *binfo)
+{
+	uint32_t i;
+	uint8_t i2c_address;
+
+	for (i = 0; i < binfo->dimm_slots_per_ctrl; i++) {
+		if (binfo->spd_i2c_addr == NULL)
+			goto error;
+		i2c_address = binfo->spd_i2c_addr[i];
+		if (get_spd(&(ctrl_dimms_spd[i]), binfo, i2c_address))
+				goto error;
+	}
+
+	return 0;
+error:
+	return 1;
+}
+
+static uint64_t step_assign_addresses(struct fsl_ddr_info_s *pinfo,
+		uint32_t dbw_cap_adj)
+{
+	uint64_t total_mem, current_mem_base, total_ctlr_mem, cap;
+	uint32_t ndimm, dw, j, found = 0;
+
+	ndimm = pinfo->board_info.dimm_slots_per_ctrl;
+	/*
+	 * If a reduced data width is requested, but the SPD
+	 * specifies a physically wider device, adjust the
+	 * computed dimm capacities accordingly before
+	 * assigning addresses.
+	 */
+	switch (pinfo->memctl_opts.data_bus_width) {
+	case 2:
+		/* 16-bit */
+		for (j = 0; j < ndimm; j++) {
+			if (!pinfo->dimm_params[j].n_ranks)
+				continue;
+			dw = pinfo->dimm_params[j].primary_sdram_width;
+			if ((dw == 72 || dw == 64)) {
+				dbw_cap_adj = 2;
+				break;
+			} else if ((dw == 40 || dw == 32)) {
+				dbw_cap_adj = 1;
+				break;
+			}
+		}
+		break;
+	case 1:
+		/* 32-bit */
+		for (j = 0; j < ndimm; j++) {
+			dw = pinfo->dimm_params[j].data_width;
+			if (pinfo->dimm_params[j].n_ranks
+			    && (dw == 72 || dw == 64)) {
+				/*
+				 * FIXME: can't really do it
+				 * like this because this just
+				 * further reduces the memory
+				 */
+				found = 1;
+				break;
+			}
+		}
+		if (found)
+			dbw_cap_adj = 1;
+		break;
+	case 0:
+		/* 64-bit */
+		break;
+	default:
+		return 1;
+	}
+
+	current_mem_base = 0ull;
+	total_mem = 0;
+	total_ctlr_mem = 0;
+	pinfo->common_timing_params.base_address = current_mem_base;
+
+	for (j = 0; j < ndimm; j++) {
+		cap = pinfo->dimm_params[j].capacity >> dbw_cap_adj;
+		pinfo->dimm_params[j].base_address = current_mem_base;
+		current_mem_base += cap;
+		total_ctlr_mem += cap;
+
+	}
+
+	pinfo->common_timing_params.total_mem = total_ctlr_mem;
+	total_mem += total_ctlr_mem;
+
+	return total_mem;
+}
+
+static uint32_t retrieve_max_size(struct fsl_ddr_cfg_regs_s *ddr_reg,
+				uint32_t ncs)
+{
+	uint32_t max_end = 0, end, i;
+
+	for (i = 0; i < ncs; i++)
+		if (ddr_reg->cs[i].config & 0x80000000) {
+			end = ddr_reg->cs[i].bnds & 0xFFF;
+			if (end > max_end)
+				max_end = end;
+		}
+
+	return max_end;
+}
+
+static uint32_t compute_dimm_param(struct fsl_ddr_info_s *pinfo, uint32_t ndimm)
+{
+	struct dimm_params_s *pdimm;
+	generic_spd_eeprom_t *spd;
+	uint32_t i, retval;
+
+	spd = &(pinfo->spd_installed_dimms[0]);
+	if (spd->mem_type == SPD_MEMTYPE_DDR3)
+		pinfo->memctl_opts.sdram_type = SDRAM_TYPE_DDR3;
+	else if (spd->mem_type == SPD_MEMTYPE_DDR2)
+		pinfo->memctl_opts.sdram_type = SDRAM_TYPE_DDR2;
+	else
+		return 1;
+
+	for (i = 0; i < ndimm; i++) {
+		spd = &(pinfo->spd_installed_dimms[i]);
+		pdimm = &(pinfo->dimm_params[i]);
+
+		retval = compute_dimm_parameters(spd, pdimm);
+
+		if (retval == 2) /* Fatal error */
+			return 1;
+	}
+
+	return 0;
+}
+
+uint64_t fsl_ddr_compute(struct fsl_ddr_info_s *pinfo)
+{
+	uint64_t total_mem = 0;
+	uint32_t ncs, ndimm, max_end = 0;
+	struct fsl_ddr_cfg_regs_s *ddr_reg;
+	struct common_timing_params_s *timing_params;
+	/* data bus width capacity adjust shift amount */
+	uint32_t dbw_capacity_adjust;
+
+	ddr_reg = &pinfo->fsl_ddr_config_reg;
+	timing_params = &pinfo->common_timing_params;
+	ncs = pinfo->board_info.cs_per_ctrl;
+	ndimm = pinfo->board_info.dimm_slots_per_ctrl;
+	dbw_capacity_adjust = 0;
+	pinfo->memctl_opts.board_info = &pinfo->board_info;
+
+	/* STEP 1:  Gather all DIMM SPD data */
+	if (fsl_ddr_get_spd(pinfo->spd_installed_dimms,
+			pinfo->memctl_opts.board_info))
+		return 0;
+
+	/* STEP 2:  Compute DIMM parameters from SPD data */
+	if (compute_dimm_param(pinfo, ndimm))
+		return 0;
+
+	/*
+	 * STEP 3: Compute a common set of timing parameters
+	 * suitable for all of the DIMMs on each memory controller
+	 */
+	compute_lowest_common_dimm_parameters(pinfo, timing_params, ndimm);
+
+	/* STEP 4:  Gather configuration requirements from user */
+	populate_memctl_options(timing_params->all_DIMMs_registered,
+			&pinfo->memctl_opts,
+			pinfo->dimm_params);
+
+	/* STEP 5:  Assign addresses to chip selects */
+	total_mem = step_assign_addresses(pinfo, dbw_capacity_adjust);
+
+	/* STEP 6:  compute controller register values */
+	if (timing_params->ndimms_present == 0)
+		memset(ddr_reg, 0, sizeof(struct fsl_ddr_cfg_regs_s));
+
+	compute_fsl_memctl_config_regs(&pinfo->memctl_opts,
+				       ddr_reg, timing_params,
+				       pinfo->dimm_params,
+				       dbw_capacity_adjust);
+
+	max_end = retrieve_max_size(ddr_reg, ncs);
+	total_mem = 1 + (((uint64_t)max_end << 24ULL) | 0xFFFFFFULL);
+
+	return total_mem;
+}
+
+/*
+ * fsl_ddr_sdram():
+ * This is the main function to initialize the memory.
+ *
+ * It returns amount of memory configured in bytes.
+ */
+phys_size_t fsl_ddr_sdram(void)
+{
+	uint64_t total_memory;
+	struct fsl_ddr_info_s info;
+
+	memset(&info, 0, sizeof(struct fsl_ddr_info_s));
+	/* Gather board information on the  memory controller and I2C bus. */
+	fsl_ddr_board_info(&info.board_info);
+
+	total_memory = fsl_ddr_compute(&info);
+
+	if (info.common_timing_params.ndimms_present == 0)
+		return 0;
+
+	fsl_ddr_set_memctl_regs(&info);
+	fsl_ddr_set_lawbar(&info.common_timing_params, LAW_TRGT_IF_DDR_1);
+
+	return total_memory;
+}