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-rw-r--r--arch/arm/cpu/arm926ejs/kirkwood/dram.c153
1 files changed, 153 insertions, 0 deletions
diff --git a/arch/arm/cpu/arm926ejs/kirkwood/dram.c b/arch/arm/cpu/arm926ejs/kirkwood/dram.c
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+++ b/arch/arm/cpu/arm926ejs/kirkwood/dram.c
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+/*
+ * (C) Copyright 2009
+ * Marvell Semiconductor <www.marvell.com>
+ * Written-by: Prafulla Wadaskar <prafulla@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 <config.h>
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/cpu.h>
+#include <asm/arch/kirkwood.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct kw_sdram_bank {
+ u32 win_bar;
+ u32 win_sz;
+};
+
+struct kw_sdram_addr_dec {
+ struct kw_sdram_bank sdram_bank[4];
+};
+
+#define KW_REG_CPUCS_WIN_ENABLE (1 << 0)
+#define KW_REG_CPUCS_WIN_WR_PROTECT (1 << 1)
+#define KW_REG_CPUCS_WIN_WIN0_CS(x) (((x) & 0x3) << 2)
+#define KW_REG_CPUCS_WIN_SIZE(x) (((x) & 0xff) << 24)
+
+/*
+ * kw_sdram_bar - reads SDRAM Base Address Register
+ */
+u32 kw_sdram_bar(enum memory_bank bank)
+{
+ struct kw_sdram_addr_dec *base =
+ (struct kw_sdram_addr_dec *)KW_REGISTER(0x1500);
+ u32 result = 0;
+ u32 enable = 0x01 & readl(&base->sdram_bank[bank].win_sz);
+
+ if ((!enable) || (bank > BANK3))
+ return 0;
+
+ result = readl(&base->sdram_bank[bank].win_bar);
+ return result;
+}
+
+/*
+ * kw_sdram_bs_set - writes SDRAM Bank size
+ */
+static void kw_sdram_bs_set(enum memory_bank bank, u32 size)
+{
+ struct kw_sdram_addr_dec *base =
+ (struct kw_sdram_addr_dec *)KW_REGISTER(0x1500);
+ /* Read current register value */
+ u32 reg = readl(&base->sdram_bank[bank].win_sz);
+
+ /* Clear window size */
+ reg &= ~KW_REG_CPUCS_WIN_SIZE(0xFF);
+
+ /* Set new window size */
+ reg |= KW_REG_CPUCS_WIN_SIZE((size - 1) >> 24);
+
+ writel(reg, &base->sdram_bank[bank].win_sz);
+}
+
+/*
+ * kw_sdram_bs - reads SDRAM Bank size
+ */
+u32 kw_sdram_bs(enum memory_bank bank)
+{
+ struct kw_sdram_addr_dec *base =
+ (struct kw_sdram_addr_dec *)KW_REGISTER(0x1500);
+ u32 result = 0;
+ u32 enable = 0x01 & readl(&base->sdram_bank[bank].win_sz);
+
+ if ((!enable) || (bank > BANK3))
+ return 0;
+ result = 0xff000000 & readl(&base->sdram_bank[bank].win_sz);
+ result += 0x01000000;
+ return result;
+}
+
+void kw_sdram_size_adjust(enum memory_bank bank)
+{
+ u32 size;
+
+ /* probe currently equipped RAM size */
+ size = get_ram_size((void *)kw_sdram_bar(bank), kw_sdram_bs(bank));
+
+ /* adjust SDRAM window size accordingly */
+ kw_sdram_bs_set(bank, size);
+}
+
+#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 = kw_sdram_bar(i);
+ gd->bd->bi_dram[i].size = kw_sdram_bs(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 */
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