diff options
Diffstat (limited to 'arch/mips/mach-ath79/ar934x/ddr.c')
-rw-r--r-- | arch/mips/mach-ath79/ar934x/ddr.c | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/arch/mips/mach-ath79/ar934x/ddr.c b/arch/mips/mach-ath79/ar934x/ddr.c new file mode 100644 index 0000000000..4621d5845c --- /dev/null +++ b/arch/mips/mach-ath79/ar934x/ddr.c @@ -0,0 +1,163 @@ +/* + * Copyright (C) 2016 Marek Vasut <marex@denx.de> + * + * Based on RAM init sequence by Piotr Dymacz <pepe2k@gmail.com> + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <asm/io.h> +#include <asm/addrspace.h> +#include <asm/types.h> +#include <mach/ar71xx_regs.h> +#include <mach/reset.h> + +DECLARE_GLOBAL_DATA_PTR; + +enum { + AR934X_SDRAM = 0, + AR934X_DDR1, + AR934X_DDR2, +}; + +struct ar934x_mem_config { + u32 config1; + u32 config2; + u32 mode; + u32 extmode; + u32 tap; +}; + +static const struct ar934x_mem_config ar934x_mem_config[] = { + [AR934X_SDRAM] = { 0x7fbe8cd0, 0x959f66a8, 0x33, 0, 0x1f1f }, + [AR934X_DDR1] = { 0x7fd48cd0, 0x99d0e6a8, 0x33, 0, 0x14 }, + [AR934X_DDR2] = { 0xc7d48cd0, 0x9dd0e6a8, 0x33, 0, 0x10012 }, +}; + +void ar934x_ddr_init(const u16 cpu_mhz, const u16 ddr_mhz, const u16 ahb_mhz) +{ + void __iomem *ddr_regs; + const struct ar934x_mem_config *memcfg; + int memtype; + u32 reg, cycle, ctl; + + ddr_regs = map_physmem(AR71XX_DDR_CTRL_BASE, AR71XX_DDR_CTRL_SIZE, + MAP_NOCACHE); + + reg = get_bootstrap(); + if (reg & AR934X_BOOTSTRAP_SDRAM_DISABLED) { /* DDR */ + if (reg & AR934X_BOOTSTRAP_DDR1) { /* DDR 1 */ + memtype = AR934X_DDR1; + cycle = 0xffff; + } else { /* DDR 2 */ + memtype = AR934X_DDR2; + if (gd->arch.rev) { + ctl = BIT(6); /* Undocumented bit :-( */ + if (reg & BIT(3)) + cycle = 0xff; + else + cycle = 0xffff; + } else { + /* Force DDR2/x16 configuratio on old chips. */ + ctl = 0; + cycle = 0xffff; /* DDR2 16bit */ + } + + writel(0xe59, ddr_regs + AR934X_DDR_REG_DDR2_CONFIG); + udelay(100); + + writel(0x10, ddr_regs + AR71XX_DDR_REG_CONTROL); + udelay(10); + + writel(0x20, ddr_regs + AR71XX_DDR_REG_CONTROL); + udelay(10); + + writel(ctl, ddr_regs + AR934X_DDR_REG_CTL_CONF); + udelay(10); + } + } else { /* SDRAM */ + memtype = AR934X_SDRAM; + cycle = 0xffffffff; + + writel(0x13b, ddr_regs + AR934X_DDR_REG_CTL_CONF); + udelay(100); + + /* Undocumented register */ + writel(0x13b, ddr_regs + 0x118); + udelay(100); + } + + memcfg = &ar934x_mem_config[memtype]; + + writel(memcfg->config1, ddr_regs + AR71XX_DDR_REG_CONFIG); + udelay(100); + + writel(memcfg->config2, ddr_regs + AR71XX_DDR_REG_CONFIG2); + udelay(100); + + writel(0x8, ddr_regs + AR71XX_DDR_REG_CONTROL); + udelay(10); + + writel(memcfg->mode | 0x100, ddr_regs + AR71XX_DDR_REG_MODE); + mdelay(1); + + writel(0x1, ddr_regs + AR71XX_DDR_REG_CONTROL); + udelay(10); + + if (memtype == AR934X_DDR2) { + writel(memcfg->mode | 0x100, ddr_regs + AR71XX_DDR_REG_EMR); + udelay(100); + + writel(0x2, ddr_regs + AR71XX_DDR_REG_CONTROL); + udelay(10); + } + + if (memtype != AR934X_SDRAM) + writel(0x402, ddr_regs + AR71XX_DDR_REG_EMR); + + udelay(100); + + writel(0x2, ddr_regs + AR71XX_DDR_REG_CONTROL); + udelay(10); + + writel(0x8, ddr_regs + AR71XX_DDR_REG_CONTROL); + udelay(10); + + writel(memcfg->mode, ddr_regs + AR71XX_DDR_REG_MODE); + udelay(100); + + writel(0x1, ddr_regs + AR71XX_DDR_REG_CONTROL); + udelay(10); + + writel(0x412c /* FIXME */, ddr_regs + AR71XX_DDR_REG_REFRESH); + udelay(100); + + writel(memcfg->tap, ddr_regs + AR71XX_DDR_REG_TAP_CTRL0); + writel(memcfg->tap, ddr_regs + AR71XX_DDR_REG_TAP_CTRL1); + + if (memtype != AR934X_SDRAM) { + if ((gd->arch.rev && (reg & BIT(3))) || !gd->arch.rev) { + writel(memcfg->tap, + ddr_regs + AR934X_DDR_REG_TAP_CTRL2); + writel(memcfg->tap, + ddr_regs + AR934X_DDR_REG_TAP_CTRL3); + } + } + + writel(cycle, ddr_regs + AR71XX_DDR_REG_RD_CYCLE); + udelay(100); + + writel(0x74444444, ddr_regs + AR934X_DDR_REG_BURST); + udelay(100); + + writel(0x222, ddr_regs + AR934X_DDR_REG_BURST2); + udelay(100); + + writel(0xfffff, ddr_regs + AR934X_DDR_REG_TIMEOUT_MAX); + udelay(100); +} + +void ddr_tap_tuning(void) +{ +} |