summaryrefslogtreecommitdiffstats
path: root/arch/arm/cpu/arm926ejs/pantheon/dram.c
diff options
context:
space:
mode:
authorTimothy Pearson <tpearson@raptorengineering.com>2017-08-23 15:54:21 -0500
committerTimothy Pearson <tpearson@raptorengineering.com>2017-08-23 15:54:21 -0500
commit0223e595f4033e91e93403a7317bcc9e47676b8f (patch)
tree2ccd7127bc343f82456b76eeb0da2d380f6eaf65 /arch/arm/cpu/arm926ejs/pantheon/dram.c
downloadast2050-uboot-0223e595f4033e91e93403a7317bcc9e47676b8f.zip
ast2050-uboot-0223e595f4033e91e93403a7317bcc9e47676b8f.tar.gz
Initial import of modified u-boot tree
Original upstream URL: git://git.denx.de/u-boot.git Original upstream GIT hash: 62c175fbb8a0f9a926c88294ea9f7e88eb898f6c
Diffstat (limited to 'arch/arm/cpu/arm926ejs/pantheon/dram.c')
-rw-r--r--arch/arm/cpu/arm926ejs/pantheon/dram.c133
1 files changed, 133 insertions, 0 deletions
diff --git a/arch/arm/cpu/arm926ejs/pantheon/dram.c b/arch/arm/cpu/arm926ejs/pantheon/dram.c
new file mode 100644
index 0000000..a3d719e
--- /dev/null
+++ b/arch/arm/cpu/arm926ejs/pantheon/dram.c
@@ -0,0 +1,133 @@
+/*
+ * (C) Copyright 2011
+ * Marvell Semiconductor <www.marvell.com>
+ * Written-by: Lei Wen <leiwen@marvell.com>,
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301 USA
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/pantheon.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/*
+ * Pantheon DRAM controller supports upto 8 banks
+ * for chip select 0 and 1
+ */
+
+/*
+ * DDR Memory Control Registers
+ * Refer Datasheet 4.4
+ */
+struct panthddr_map_registers {
+ u32 cs; /* Memory Address Map Register -CS */
+ u32 pad[3];
+};
+
+struct panthddr_registers {
+ u8 pad[0x100 - 0x000];
+ struct panthddr_map_registers mmap[2];
+};
+
+/*
+ * panth_sdram_base - reads SDRAM Base Address Register
+ */
+u32 panth_sdram_base(int chip_sel)
+{
+ struct panthddr_registers *ddr_regs =
+ (struct panthddr_registers *)PANTHEON_DRAM_BASE;
+ u32 result = 0;
+ u32 CS_valid = 0x01 & readl(&ddr_regs->mmap[chip_sel].cs);
+
+ if (!CS_valid)
+ return 0;
+
+ result = readl(&ddr_regs->mmap[chip_sel].cs) & 0xFF800000;
+ return result;
+}
+
+/*
+ * panth_sdram_size - reads SDRAM size
+ */
+u32 panth_sdram_size(int chip_sel)
+{
+ struct panthddr_registers *ddr_regs =
+ (struct panthddr_registers *)PANTHEON_DRAM_BASE;
+ u32 result = 0;
+ u32 CS_valid = 0x01 & readl(&ddr_regs->mmap[chip_sel].cs);
+
+ if (!CS_valid)
+ return 0;
+
+ result = readl(&ddr_regs->mmap[chip_sel].cs);
+ result = (result >> 16) & 0xF;
+ if (result < 0x7) {
+ printf("Unknown DRAM Size\n");
+ return -1;
+ } else {
+ return ((0x8 << (result - 0x7)) * 1024 * 1024);
+ }
+}
+
+#ifndef CONFIG_SYS_BOARD_DRAM_INIT
+int dram_init(void)
+{
+ int i;
+
+ gd->ram_size = 0;
+ for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
+ gd->bd->bi_dram[i].start = panth_sdram_base(i);
+ gd->bd->bi_dram[i].size = panth_sdram_size(i);
+ /*
+ * It is assumed that all memory banks are consecutive
+ * and without gaps.
+ * If the gap is found, ram_size will be reported for
+ * consecutive memory only
+ */
+ if (gd->bd->bi_dram[i].start != gd->ram_size)
+ break;
+
+ gd->ram_size += gd->bd->bi_dram[i].size;
+
+ }
+
+ for (; i < CONFIG_NR_DRAM_BANKS; i++) {
+ /*
+ * If above loop terminated prematurely, we need to set
+ * remaining banks' start address & size as 0. Otherwise other
+ * u-boot functions and Linux kernel gets wrong values which
+ * could result in crash
+ */
+ gd->bd->bi_dram[i].start = 0;
+ gd->bd->bi_dram[i].size = 0;
+ }
+ return 0;
+}
+
+/*
+ * If this function is not defined here,
+ * board.c alters dram bank zero configuration defined above.
+ */
+void dram_init_banksize(void)
+{
+ dram_init();
+}
+#endif /* CONFIG_SYS_BOARD_DRAM_INIT */
OpenPOWER on IntegriCloud