powerpc/mpc8xxx: Add 16-bit support for DDR3
Add support for 16-bit DDR bus. Also deal with system using 64- and 32-bit
DDR devices.
Signed-off-by: York Sun <yorksun@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/arch/powerpc/cpu/mpc8xxx/ddr/main.c b/arch/powerpc/cpu/mpc8xxx/ddr/main.c
index c8fa123..62a73dd 100644
--- a/arch/powerpc/cpu/mpc8xxx/ddr/main.c
+++ b/arch/powerpc/cpu/mpc8xxx/ddr/main.c
@@ -174,7 +174,19 @@
switch (pinfo->memctl_opts[i].data_bus_width) {
case 2:
/* 16-bit */
- printf("can't handle 16-bit mode yet\n");
+ for (j = 0; j < CONFIG_DIMM_SLOTS_PER_CTLR; j++) {
+ unsigned int dw;
+ if (!pinfo->dimm_params[i][j].n_ranks)
+ continue;
+ dw = pinfo->dimm_params[i][j].primary_sdram_width;
+ if ((dw == 72 || dw == 64)) {
+ dbw_cap_adj[i] = 2;
+ break;
+ } else if ((dw == 40 || dw == 32)) {
+ dbw_cap_adj[i] = 1;
+ break;
+ }
+ }
break;
case 1:
diff --git a/arch/powerpc/cpu/mpc8xxx/ddr/options.c b/arch/powerpc/cpu/mpc8xxx/ddr/options.c
index 80c7046..02efe58 100644
--- a/arch/powerpc/cpu/mpc8xxx/ddr/options.c
+++ b/arch/powerpc/cpu/mpc8xxx/ddr/options.c
@@ -438,7 +438,8 @@
popts->OTF_burst_chop_en = 0; /* on-the-fly burst chop disable */
popts->burst_length = DDR_BL8; /* Fixed 8-beat burst len */
#else
- if (popts->data_bus_width == 1) { /* 32-bit bus */
+ if ((popts->data_bus_width == 1) || (popts->data_bus_width == 2)) {
+ /* 32-bit or 16-bit bus */
popts->OTF_burst_chop_en = 0;
popts->burst_length = DDR_BL8;
} else {
diff --git a/arch/powerpc/include/asm/fsl_ddr_sdram.h b/arch/powerpc/include/asm/fsl_ddr_sdram.h
index 127a840..1778cc5 100644
--- a/arch/powerpc/include/asm/fsl_ddr_sdram.h
+++ b/arch/powerpc/include/asm/fsl_ddr_sdram.h
@@ -181,6 +181,9 @@
unsigned int all_DIMMs_minimum_tRCD_ps;
} memctl_options_partial_t;
+#define DDR_DATA_BUS_WIDTH_64 0
+#define DDR_DATA_BUS_WIDTH_32 1
+#define DDR_DATA_BUS_WIDTH_16 2
/*
* Generalized parameters for memory controller configuration,
* might be a little specific to the FSL memory controller