[U-Boot] [PATCH 03/10] ddr: altera: s10: Add multiple memory banks support

[Ley Foon Tan]

Setup bank start address and size based on total SDRAM
memory size calculated from hardware. Update sdram_size_check()
to support multiple banks.

Stratix10 supports up to 2 memory banks.

Bank 0: Address 0, size 2GB
Bank 1: Address 0x100000000, size 124GB

Signed-off-by: Dalon Westergreen <dalon.westergreen at intel.com>
Signed-off-by: Ley Foon Tan <ley.foon.tan at intel.com>
---
 .../arm/mach-socfpga/include/mach/sdram_s10.h |  1 +
 drivers/ddr/altera/sdram_s10.c                | 93 ++++++++++++++++++-
 2 files changed, 91 insertions(+), 3 deletions(-)

diff --git a/arch/arm/mach-socfpga/include/mach/sdram_s10.h b/arch/arm/mach-socfpga/include/mach/sdram_s10.h
index ca68594445..89e355010d 100644
--- a/arch/arm/mach-socfpga/include/mach/sdram_s10.h
+++ b/arch/arm/mach-socfpga/include/mach/sdram_s10.h
@@ -10,6 +10,7 @@
 phys_size_t sdram_calculate_size(void);
 int sdram_mmr_init_full(unsigned int sdr_phy_reg);
 int sdram_calibration_full(void);
+void setup_memory_banks(phys_addr_t bank_addr[], phys_size_t bank_size[]);
 
 #define DDR_TWR				15
 #define DDR_READ_LATENCY_DELAY		40
diff --git a/drivers/ddr/altera/sdram_s10.c b/drivers/ddr/altera/sdram_s10.c
index 8895813440..ae4e5ea2fd 100644
--- a/drivers/ddr/altera/sdram_s10.c
+++ b/drivers/ddr/altera/sdram_s10.c
@@ -13,6 +13,7 @@
 #include <asm/arch/sdram_s10.h>
 #include <asm/arch/system_manager.h>
 #include <asm/arch/reset_manager.h>
+#include <linux/sizes.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -134,17 +135,100 @@ static int poll_hmc_clock_status(void)
 				 SYSMGR_HMC_CLK_STATUS_MSK, true, 1000, false);
 }
 
-static void sdram_size_check(void)
+static void sdram_size_check(phys_addr_t bank_start[], phys_size_t bank_size[])
 {
+	phys_size_t total_ram_check = 0;
+	phys_size_t ram_check = 0;
+	int bank;
+
 	/* Sanity check ensure correct SDRAM size specified */
 	debug("DDR: Running SDRAM size sanity check\n");
-	if (get_ram_size(0, gd->ram_size) != gd->ram_size) {
+
+	for (bank = 0; bank < CONFIG_NR_DRAM_BANKS; bank++) {
+		while (ram_check < bank_size[bank]) {
+			ram_check += get_ram_size((void *)(bank_start[bank]
+							   + ram_check),
+							   (phys_size_t)SZ_1G);
+		}
+		total_ram_check += ram_check;
+		ram_check = 0;
+	}
+
+	if (total_ram_check != gd->ram_size) {
 		puts("DDR: SDRAM size check failed!\n");
 		hang();
 	}
+
 	debug("DDR: SDRAM size check passed!\n");
 }
 
+void setup_memory_banks(phys_addr_t bank_addr[], phys_size_t bank_size[])
+{
+	phys_size_t ram_alias;
+
+	bank_addr[0] = CONFIG_SYS_SDRAM_BASE;
+	bank_size[0] = min((phys_size_t)SZ_2G, (phys_size_t)gd->ram_size);
+
+	if (CONFIG_NR_DRAM_BANKS > 1) {
+		if (gd->ram_size > ((phys_size_t)SZ_2G * (phys_size_t)32)) {
+			/* With memories > 64GB it is not possible to
+			 * access the entire memory. You cannot avoid
+			 * the 2GB IO hole from 2GB to 4GB in the HPS
+			 * memory space. The dram banks must be configured
+			 * as :
+			 * dram[0].start = 0x0
+			 * dram[0].size = SZ_2GB
+			 * dram[1].start = SZ_2GB << 1 (or 4GB)
+			 * dram[1].size = gd->ram_size - SZ_2G
+			 */
+			bank_addr[1] = (phys_addr_t)SZ_2G +
+				(phys_addr_t)SZ_2G;
+			bank_size[1] = gd->ram_size - SZ_2G;
+
+			/* reduce ram size as useable space is smaller.
+			 * We cannot avoid the IO hole.
+			 */
+			gd->ram_size -= SZ_2G;
+
+		} else if (gd->ram_size > SZ_2G) {
+			/* We can use that the DRAM address space
+			 * is repeatedly aliased in the overall
+			 * 128GB of address space as the SDRAM NOC
+			 * ignores unused upper address bits.
+			 *
+			 * This means, a 4GB DDR is replicated every
+			 * 4GB in the address, and a 16GB DDR every
+			 * 16GB.
+			 *
+			 * So, we can access the entire memory, for
+			 * the 4GB case:
+			 * dram[0].start = 0x0
+			 * dram[0].size = SZ_2GB
+			 * dram[1].start = SZ_2GB << 1 + SZ_2GB (or 6GB)
+			 * dram[1].size = gd->ram_size - SZ_2G
+			 *
+			 * more interestingly, the 3GB case would be the same.
+			 */
+
+			/* Now we need to find the appropriate alias
+			 * location.
+			 */
+			ram_alias = SZ_2G;
+			while (ram_alias < gd->ram_size)
+				ram_alias = ram_alias << 1;
+
+			bank_addr[1] = ram_alias + SZ_2G;
+			bank_size[1] = gd->ram_size - SZ_2G;
+		} else {
+			/* Here the map is simple as all memory fits in the
+			 * lower 2GB window.
+			 */
+			bank_addr[1] = 0;
+			bank_size[1] = 0;
+		}
+	}
+}
+
 /**
  * sdram_mmr_init_full() - Function to initialize SDRAM MMR
  *
@@ -155,6 +239,8 @@ int sdram_mmr_init_full(unsigned int unused)
 	u32 update_value, io48_value, ddrioctl;
 	u32 i;
 	int ret;
+	phys_addr_t bank_start[CONFIG_NR_DRAM_BANKS];
+	phys_size_t bank_size[CONFIG_NR_DRAM_BANKS];
 
 	/* Enable access to DDR from CPU master */
 	clrbits_le32(CCU_REG_ADDR(CCU_CPU0_MPRT_ADBASE_DDRREG),
@@ -351,6 +437,7 @@ int sdram_mmr_init_full(unsigned int unused)
 		gd->ram_size = size;
 
 	printf("DDR: %d MiB\n", (int)(gd->ram_size >> 20));
+	setup_memory_banks(bank_start, bank_size);
 
 	/* Enable or disable the SDRAM ECC */
 	if (CTRLCFG1_CFG_CTRL_EN_ECC(ctrlcfg1)) {
@@ -374,7 +461,7 @@ int sdram_mmr_init_full(unsigned int unused)
 			      DDR_HMC_ECCCTL2_AWB_EN_SET_MSK));
 	}
 
-	sdram_size_check();
+	sdram_size_check(bank_start, bank_size);
 
 	debug("DDR: HMC init success\n");
 	return 0;
-- 
2.19.0