diff options
Diffstat (limited to 'arch/arm/cpu/arm926ejs/kirkwood/dram.c')
-rw-r--r-- | arch/arm/cpu/arm926ejs/kirkwood/dram.c | 153 |
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 new file mode 100644 index 0000000..807894f --- /dev/null +++ b/arch/arm/cpu/arm926ejs/kirkwood/dram.c @@ -0,0 +1,153 @@ +/* + * (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 */ |