ppc/85xx: 32bit DDR changes for P1020/P1011

The P1020/P1011 SOCs support max 32bit DDR width as opposed to P2020/P2010
where max DDR data width supported is 64bit.

As a next step the DDR data width initialization would be made more dynamic
with more flexibility from the board perspective and user choice.
Going forward we would also remove the hardcodings for platforms with onboard
memories and try to use the FSL SPD code for DDR initialization.

Signed-off-by: Poonam Aggrwal <poonam.aggrwal@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

board/freescale/p1_p2_rdb/ddr.c

@@ -23,10 +23,13 @@
 #include <common.h>
 #include <asm/mmu.h>
 #include <asm/immap_85xx.h>
+#include <asm/processor.h>
 #include <asm/fsl_ddr_sdram.h>
 #include <asm/io.h>
 #include <asm/fsl_law.h>
 
+DECLARE_GLOBAL_DATA_PTR;
+
 extern void fsl_ddr_set_memctl_regs(const fsl_ddr_cfg_regs_t *regs,
 				   unsigned int ctrl_num);
 
@@ -203,24 +206,40 @@ phys_size_t fixed_sdram (void)
 {
 	sys_info_t sysinfo;
 	char buf[32];
+	fsl_ddr_cfg_regs_t *ddr_cfg_regs = NULL;
+	size_t ddr_size;
+	struct cpu_type *cpu;
 
 	get_sys_info(&sysinfo);
 	printf("Configuring DDR for %s MT/s data rate\n",
 				strmhz(buf, sysinfo.freqDDRBus));
 
 	if(sysinfo.freqDDRBus <= DATARATE_400MHZ)
-		fsl_ddr_set_memctl_regs(&ddr_cfg_regs_400, 0);
+		ddr_cfg_regs = &ddr_cfg_regs_400;
 	else if(sysinfo.freqDDRBus <= DATARATE_533MHZ)
-		fsl_ddr_set_memctl_regs(&ddr_cfg_regs_533, 0);
+		ddr_cfg_regs = &ddr_cfg_regs_533;
 	else if(sysinfo.freqDDRBus <= DATARATE_667MHZ)
-		fsl_ddr_set_memctl_regs(&ddr_cfg_regs_667, 0);
+		ddr_cfg_regs = &ddr_cfg_regs_667;
 	else if(sysinfo.freqDDRBus <= DATARATE_800MHZ)
-		fsl_ddr_set_memctl_regs(&ddr_cfg_regs_800, 0);
+		ddr_cfg_regs = &ddr_cfg_regs_800;
 	else
 		panic("Unsupported DDR data rate %s MT/s data rate\n",
 					strmhz(buf, sysinfo.freqDDRBus));
 
-	return CONFIG_SYS_SDRAM_SIZE * 1024 * 1024;
+	cpu = gd->cpu;
+	/* P1020 and it's derivatives support max 32bit DDR width */
+	if(cpu->soc_ver == SVR_P1020 || cpu->soc_ver == SVR_P1020_E ||
+		cpu->soc_ver == SVR_P1011 || cpu->soc_ver == SVR_P1011_E) {
+		ddr_cfg_regs->ddr_sdram_cfg |= SDRAM_CFG_32_BE;
+		ddr_cfg_regs->cs[0].bnds = 0x0000001F;
+		ddr_size = (CONFIG_SYS_SDRAM_SIZE * 1024 * 1024 / 2);
+	}
+	else
+		ddr_size = CONFIG_SYS_SDRAM_SIZE * 1024 * 1024;
+
+	fsl_ddr_set_memctl_regs(ddr_cfg_regs, 0);
+
+	return ddr_size;
 }
 
 phys_size_t initdram(int board_type)