rockchip: sdram: add dram bank with usable memory beyond 4GB

Add a second dram bank of usable memory beyond the blob of space for
peripheral near 4GB. Any memory that exists beyond the 4GB mark is added
to the second bank.

Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>

diff --git a/arch/arm/mach-rockchip/sdram.c b/arch/arm/mach-rockchip/sdram.c
index 91951e4..1d17a74 100644 (file)
--- a/arch/arm/mach-rockchip/sdram.c
+++ b/arch/arm/mach-rockchip/sdram.c
@@ -37,13 +37,19 @@ struct tos_parameter_t {
 
 int dram_init_banksize(void)
 {
-       size_t top = min((unsigned long)(gd->ram_size + CFG_SYS_SDRAM_BASE),
-                        (unsigned long)(gd->ram_top));
+       size_t ram_top = (unsigned long)(gd->ram_size + CFG_SYS_SDRAM_BASE);
+       size_t top = min((unsigned long)ram_top, (unsigned long)(gd->ram_top));
 
 #ifdef CONFIG_ARM64
        /* Reserve 0x200000 for ATF bl31 */
        gd->bd->bi_dram[0].start = 0x200000;
        gd->bd->bi_dram[0].size = top - gd->bd->bi_dram[0].start;
+
+       /* Add usable memory beyond the blob of space for peripheral near 4GB */
+       if (ram_top > SZ_4G && top < SZ_4G) {
+               gd->bd->bi_dram[1].start = SZ_4G;
+               gd->bd->bi_dram[1].size = ram_top - gd->bd->bi_dram[1].start;
+       }
 #else
 #ifdef CONFIG_SPL_OPTEE_IMAGE
        struct tos_parameter_t *tos_parameter;
@@ -181,7 +187,7 @@ size_t rockchip_sdram_size(phys_addr_t reg)
         *   2. update board_get_usable_ram_top() and dram_init_banksize()
         *   to reserve memory for peripheral space after previous update.
         */
-       if (size_mb > (SDRAM_MAX_SIZE >> 20))
+       if (!IS_ENABLED(CONFIG_ARM64) && size_mb > (SDRAM_MAX_SIZE >> 20))
                size_mb = (SDRAM_MAX_SIZE >> 20);
 
        return (size_t)size_mb << 20;