mpc83xx: mpc8360emds: rework LBC SDRAM setup

Currently 64M of LBC SDRAM are mapped at 0xF0000000 which makes
it difficult to use (b/c then the memory is discontinuous and
there is quite big memory hole between the DDR/SDRAM regions).

This patch reworks LBC SDRAM setup so that now we dynamically
place the LBC SDRAM near the DDR (or at 0x0 if there isn't any
DDR memory).

With this patch we're able to:

- Boot without external DDR memory;
- Use most "DDR + SDRAM" setups without need to support for
  sparse/discontinuous memory model in the software.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>

1 files changed, 27 insertions, 12 deletions

diff --git a/board/freescale/mpc8360emds/mpc8360emds.c b/board/freescale/mpc8360emds/mpc8360emds.c
index fc0a0e5..b5cf714 100644
--- a/board/freescale/mpc8360emds/mpc8360emds.c
+++ b/board/freescale/mpc8360emds/mpc8360emds.c
@@ -120,7 +120,7 @@ int board_early_init_r(void)
 extern void ddr_enable_ecc(unsigned int dram_size);
 #endif
 int fixed_sdram(void);
-void sdram_init(void);
+static int sdram_init(unsigned int base);
 
 phys_size_t initdram(int board_type)
 {
@@ -147,7 +147,7 @@ phys_size_t initdram(int board_type)
 	/*
 	 * Initialize SDRAM if it is on local bus.
 	 */
-	sdram_init();
+	msize += sdram_init(msize * 1024 * 1024);
 
 	/* return total bus SDRAM size(bytes)  -- DDR */
 	return (msize * 1024 * 1024);
@@ -219,23 +219,32 @@ int checkboard(void)
 /*
  * if MPC8360EMDS is soldered with SDRAM
  */
-#if defined(CONFIG_SYS_BR2_PRELIM)  \
-	&& defined(CONFIG_SYS_OR2_PRELIM) \
-	&& defined(CONFIG_SYS_LBLAWBAR2_PRELIM) \
-	&& defined(CONFIG_SYS_LBLAWAR2_PRELIM)
+#ifdef CONFIG_SYS_LB_SDRAM
 /*
  * Initialize SDRAM memory on the Local Bus.
  */
 
-void sdram_init(void)
+static int sdram_init(unsigned int base)
 {
 	volatile immap_t *immap = (immap_t *) CONFIG_SYS_IMMR;
 	volatile lbus83xx_t *lbc = &immap->lbus;
-	uint *sdram_addr = (uint *) CONFIG_SYS_LBC_SDRAM_BASE;
+	const int sdram_size = CONFIG_SYS_LBC_SDRAM_SIZE * 1024 * 1024;
+	int rem = base % sdram_size;
+	uint *sdram_addr;
 
+	/* window base address should be aligned to the window size */
+	if (rem)
+		base = base - rem + sdram_size;
+
+	sdram_addr = (uint *)base;
 	/*
-	 * Setup SDRAM Base and Option Registers, already done in cpu_init.c
+	 * Setup SDRAM Base and Option Registers
 	 */
+	immap->lbus.bank[2].br = base | CONFIG_SYS_BR2;
+	immap->lbus.bank[2].or = CONFIG_SYS_OR2;
+	immap->sysconf.lblaw[2].bar = base;
+	immap->sysconf.lblaw[2].ar = CONFIG_SYS_LBLAWAR2;
+
 	/*setup mtrpt, lsrt and lbcr for LB bus */
 	lbc->lbcr = CONFIG_SYS_LBC_LBCR;
 	lbc->mrtpr = CONFIG_SYS_LBC_MRTPR;
@@ -284,11 +293,17 @@ void sdram_init(void)
 	asm("sync");
 	*sdram_addr = 0xff;
 	udelay(100);
+
+	/*
+	 * In non-aligned case we don't [normally] use that memory because
+	 * there is a hole.
+	 */
+	if (rem)
+		return 0;
+	return CONFIG_SYS_LBC_SDRAM_SIZE;
 }
 #else
-void sdram_init(void)
-{
-}
+static int sdram_init(unsigned int base) { return 0; }
 #endif
 
 #if defined(CONFIG_OF_BOARD_SETUP)