From: Olof Johansson Date: Mon, 17 Oct 2011 23:05:22 +0000 (-0700) Subject: ARM: tegra: emc: device tree support X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=941b8db1df8bfc29a88fc8e3e203289d84a3f64d;p=linux-beck.git ARM: tegra: emc: device tree support Add device tree support to the emc driver, filling in the platform data based on the DT bindings. Changes since v1: * Unmangled some messed up patch squashes, moving changes to earlier patches * Flipped an of_property_read_u32 return value test * Clarified clock settings message on case where no table is provided Signed-off-by: Olof Johansson Acked-by: Stephen Warren --- diff --git a/arch/arm/mach-tegra/tegra2_emc.c b/arch/arm/mach-tegra/tegra2_emc.c index e6229bbbb83a..52df6ca36292 100644 --- a/arch/arm/mach-tegra/tegra2_emc.c +++ b/arch/arm/mach-tegra/tegra2_emc.c @@ -21,12 +21,14 @@ #include #include #include +#include #include #include #include #include "tegra2_emc.h" +#include "fuse.h" #ifdef CONFIG_TEGRA_EMC_SCALING_ENABLE static bool emc_enable = true; @@ -176,6 +178,126 @@ int tegra_emc_set_rate(unsigned long rate) return 0; } +#ifdef CONFIG_OF +static struct device_node *tegra_emc_ramcode_devnode(struct device_node *np) +{ + struct device_node *iter; + u32 reg; + + for_each_child_of_node(np, iter) { + if (of_property_read_u32(np, "nvidia,ram-code", ®)) + continue; + if (reg == tegra_bct_strapping) + return of_node_get(iter); + } + + return NULL; +} + +static struct tegra_emc_pdata *tegra_emc_dt_parse_pdata( + struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct device_node *tnp, *iter; + struct tegra_emc_pdata *pdata; + int ret, i, num_tables; + + if (!np) + return NULL; + + if (of_find_property(np, "nvidia,use-ram-code", NULL)) { + tnp = tegra_emc_ramcode_devnode(np); + if (!tnp) + dev_warn(&pdev->dev, + "can't find emc table for ram-code 0x%02x\n", + tegra_bct_strapping); + } else + tnp = of_node_get(np); + + if (!tnp) + return NULL; + + num_tables = 0; + for_each_child_of_node(tnp, iter) + if (of_device_is_compatible(iter, "nvidia,tegra20-emc-table")) + num_tables++; + + if (!num_tables) { + pdata = NULL; + goto out; + } + + pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); + pdata->tables = devm_kzalloc(&pdev->dev, + sizeof(*pdata->tables) * num_tables, + GFP_KERNEL); + + i = 0; + for_each_child_of_node(tnp, iter) { + u32 prop; + + ret = of_property_read_u32(iter, "clock-frequency", &prop); + if (ret) { + dev_err(&pdev->dev, "no clock-frequency in %s\n", + iter->full_name); + continue; + } + pdata->tables[i].rate = prop; + + ret = of_property_read_u32_array(iter, "nvidia,emc-registers", + pdata->tables[i].regs, + TEGRA_EMC_NUM_REGS); + if (ret) { + dev_err(&pdev->dev, + "malformed emc-registers property in %s\n", + iter->full_name); + continue; + } + + i++; + } + pdata->num_tables = i; + +out: + of_node_put(tnp); + return pdata; +} +#else +static struct tegra_emc_pdata *tegra_emc_dt_parse_pdata( + struct platform_device *pdev) +{ + return NULL; +} +#endif + +static struct tegra_emc_pdata __devinit *tegra_emc_fill_pdata(struct platform_device *pdev) +{ + struct clk *c = clk_get_sys(NULL, "emc"); + struct tegra_emc_pdata *pdata; + unsigned long khz; + int i; + + WARN_ON(pdev->dev.platform_data); + BUG_ON(IS_ERR_OR_NULL(c)); + + pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); + pdata->tables = devm_kzalloc(&pdev->dev, sizeof(*pdata->tables), + GFP_KERNEL); + + pdata->tables[0].rate = clk_get_rate(c); + + for (i = 0; i < TEGRA_EMC_NUM_REGS; i++) + pdata->tables[0].regs[i] = emc_readl(emc_reg_addr[i]); + + pdata->num_tables = 1; + + khz = pdata->tables[0].rate / 1000; + dev_info(&pdev->dev, "no tables provided, using %ld kHz emc, " + "%ld kHz mem\n", khz, khz/2); + + return pdata; +} + static int __devinit tegra_emc_probe(struct platform_device *pdev) { struct tegra_emc_pdata *pdata; @@ -186,13 +308,6 @@ static int __devinit tegra_emc_probe(struct platform_device *pdev) return -ENODEV; } - pdata = pdev->dev.platform_data; - - if (!pdata) { - dev_err(&pdev->dev, "missing platform data\n"); - return -ENXIO; - } - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) { dev_err(&pdev->dev, "missing register base\n"); @@ -204,15 +319,32 @@ static int __devinit tegra_emc_probe(struct platform_device *pdev) dev_err(&pdev->dev, "failed to remap registers\n"); return -ENOMEM; } + + pdata = pdev->dev.platform_data; + + if (!pdata) + pdata = tegra_emc_dt_parse_pdata(pdev); + + if (!pdata) + pdata = tegra_emc_fill_pdata(pdev); + + pdev->dev.platform_data = pdata; + emc_pdev = pdev; return 0; } +static struct of_device_id tegra_emc_of_match[] __devinitdata = { + { .compatible = "nvidia,tegra20-emc", }, + { }, +}; + static struct platform_driver tegra_emc_driver = { .driver = { .name = "tegra-emc", .owner = THIS_MODULE, + .of_match_table = tegra_emc_of_match, }, .probe = tegra_emc_probe, };