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authorOlof Johansson <olof@lixom.net>2011-10-17 16:05:22 -0700
committerOlof Johansson <olof@lixom.net>2012-02-06 18:24:59 -0800
commit941b8db1df8bfc29a88fc8e3e203289d84a3f64d (patch)
treebfed645eff99faf77ffb96c1b3656a5bf09d8c68 /arch/arm/mach-tegra/tegra2_emc.c
parent17711dbf4788ded84470941ff63a7029f73ca654 (diff)
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 <olof@lixom.net> Acked-by: Stephen Warren <swarren@nvidia.com>
Diffstat (limited to 'arch/arm/mach-tegra/tegra2_emc.c')
-rw-r--r--arch/arm/mach-tegra/tegra2_emc.c146
1 files changed, 139 insertions, 7 deletions
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 <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
+#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/platform_data/tegra_emc.h>
#include <mach/iomap.h>
#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", &reg))
+ 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,
};