[U-Boot] [RESEND PATCH 10/14] ram: stm32: add memory mapping selection support

patrice.chotard at st.com
2017-12-12T08:49:41Z

This allows to controls the memory internal mapping at
address 0x0000 0000.
We can either map at 0x0000 0000 :
_ main flash memory
_ system flash memory
_ FMC bank1 (NOR/PSRAM 1 and 2)
_ embedded SRAM
_ FMC/SDRAM bank1

This is needed for future STM32F469-disco board

Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
---
drivers/ram/stm32_sdram.c | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)

diff --git a/drivers/ram/stm32_sdram.c b/drivers/ram/stm32_sdram.c
index 6e92b22..ec2edd6 100644
--- a/drivers/ram/stm32_sdram.c
+++ b/drivers/ram/stm32_sdram.c
@@ -11,6 +11,9 @@
#include <ram.h>
#include <asm/io.h>

+#define MEM_MODE_MASK GENMASK(2, 0)
+#define NOT_FOUND 0xff
+
DECLARE_GLOBAL_DATA_PTR;

struct stm32_fmc_regs {
@@ -253,9 +256,31 @@ static int stm32_fmc_ofdata_to_platdata(struct udevice *dev)
{
struct stm32_sdram_params *params = dev_get_platdata(dev);
struct bank_params *bank_params;
+ struct ofnode_phandle_args args;
+ u32 *syscfg_base;
+ u32 mem_remap;
ofnode bank_node;
char *bank_name;
u8 bank = 0;
+ int ret;
+
+ mem_remap = dev_read_u32_default(dev, "st,mem_remap", NOT_FOUND);
+ if (mem_remap != NOT_FOUND) {
+ ret = dev_read_phandle_with_args(dev, "st,syscfg", NULL, 0, 0,
+ &args);
+ if (ret) {
+ debug("%s: can't find syscon device (%d)\n", __func__,
+ ret);
+ return ret;
+ }
+
+ syscfg_base = (u32 *)ofnode_get_addr(args.node);
+
+ /* set memory mapping selection */
+ clrsetbits_le32(syscfg_base, MEM_MODE_MASK, mem_remap);
+ } else {
+ debug("%s: cannot find st,mem_remap property\n", __func__);
+ }

dev_for_each_subnode(bank_node, dev) {
/* extract the bank index from DT */
--
1.9.1