diff options
author | Olof Johansson <olof@lixom.net> | 2011-10-16 23:54:51 (GMT) |
---|---|---|
committer | Olof Johansson <olof@lixom.net> | 2012-02-07 02:24:59 (GMT) |
commit | 17711dbf4788ded84470941ff63a7029f73ca654 (patch) | |
tree | 2a728096b0c3c67299bf47fb9a0069c7fbb9e67a /arch/arm/mach-tegra | |
parent | dee47183301983139fd0ed784d0defe0ba08f8f6 (diff) | |
download | linux-fsl-qoriq-17711dbf4788ded84470941ff63a7029f73ca654.tar.xz |
ARM: tegra: emc: convert tegra2_emc to a platform driver
This is the first step in making it device-tree aware and get rid of the
in-kernel EMC tables (of which there are none in mainline, thankfully).
Changes since v3:
* moved to devm_request_and_ioremap() in probe()
Changes since v2:
* D'oh -- missed a couple of variables that were added, never used and then
later removed in a later patch.
Changes since v1:
* Fixed messed up indentation
* Removed code that should be gone (was added here and removed later in series)
Signed-off-by: Olof Johansson <olof@lixom.net>
Acked-by: Stephen Warren <swarren@nvidia.com>
Diffstat (limited to 'arch/arm/mach-tegra')
-rw-r--r-- | arch/arm/mach-tegra/tegra2_emc.c | 92 | ||||
-rw-r--r-- | arch/arm/mach-tegra/tegra2_emc.h | 11 |
2 files changed, 73 insertions, 30 deletions
diff --git a/arch/arm/mach-tegra/tegra2_emc.c b/arch/arm/mach-tegra/tegra2_emc.c index 0f7ae6e..e6229bb 100644 --- a/arch/arm/mach-tegra/tegra2_emc.c +++ b/arch/arm/mach-tegra/tegra2_emc.c @@ -16,10 +16,13 @@ */ #include <linux/kernel.h> +#include <linux/device.h> #include <linux/clk.h> #include <linux/err.h> #include <linux/io.h> #include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/platform_data/tegra_emc.h> #include <mach/iomap.h> @@ -32,18 +35,17 @@ static bool emc_enable; #endif module_param(emc_enable, bool, 0644); -static void __iomem *emc = IO_ADDRESS(TEGRA_EMC_BASE); -static const struct tegra_emc_table *tegra_emc_table; -static int tegra_emc_table_size; +static struct platform_device *emc_pdev; +static void __iomem *emc_regbase; static inline void emc_writel(u32 val, unsigned long addr) { - writel(val, emc + addr); + writel(val, emc_regbase + addr); } static inline u32 emc_readl(unsigned long addr) { - return readl(emc + addr); + return readl(emc_regbase + addr); } static const unsigned long emc_reg_addr[TEGRA_EMC_NUM_REGS] = { @@ -98,15 +100,15 @@ static const unsigned long emc_reg_addr[TEGRA_EMC_NUM_REGS] = { /* Select the closest EMC rate that is higher than the requested rate */ long tegra_emc_round_rate(unsigned long rate) { + struct tegra_emc_pdata *pdata; int i; int best = -1; unsigned long distance = ULONG_MAX; - if (!tegra_emc_table) + if (!emc_pdev) return -EINVAL; - if (!emc_enable) - return -EINVAL; + pdata = emc_pdev->dev.platform_data; pr_debug("%s: %lu\n", __func__, rate); @@ -116,10 +118,10 @@ long tegra_emc_round_rate(unsigned long rate) */ rate = rate / 2 / 1000; - for (i = 0; i < tegra_emc_table_size; i++) { - if (tegra_emc_table[i].rate >= rate && - (tegra_emc_table[i].rate - rate) < distance) { - distance = tegra_emc_table[i].rate - rate; + for (i = 0; i < pdata->num_tables; i++) { + if (pdata->tables[i].rate >= rate && + (pdata->tables[i].rate - rate) < distance) { + distance = pdata->tables[i].rate - rate; best = i; } } @@ -127,9 +129,9 @@ long tegra_emc_round_rate(unsigned long rate) if (best < 0) return -EINVAL; - pr_debug("%s: using %lu\n", __func__, tegra_emc_table[best].rate); + pr_debug("%s: using %lu\n", __func__, pdata->tables[best].rate); - return tegra_emc_table[best].rate * 2 * 1000; + return pdata->tables[best].rate * 2 * 1000; } /* @@ -142,37 +144,81 @@ long tegra_emc_round_rate(unsigned long rate) */ int tegra_emc_set_rate(unsigned long rate) { + struct tegra_emc_pdata *pdata; int i; int j; - if (!tegra_emc_table) + if (!emc_pdev) return -EINVAL; + pdata = emc_pdev->dev.platform_data; + /* * The EMC clock rate is twice the bus rate, and the bus rate is * measured in kHz */ rate = rate / 2 / 1000; - for (i = 0; i < tegra_emc_table_size; i++) - if (tegra_emc_table[i].rate == rate) + for (i = 0; i < pdata->num_tables; i++) + if (pdata->tables[i].rate == rate) break; - if (i >= tegra_emc_table_size) + if (i >= pdata->num_tables) return -EINVAL; pr_debug("%s: setting to %lu\n", __func__, rate); for (j = 0; j < TEGRA_EMC_NUM_REGS; j++) - emc_writel(tegra_emc_table[i].regs[j], emc_reg_addr[j]); + emc_writel(pdata->tables[i].regs[j], emc_reg_addr[j]); + + emc_readl(pdata->tables[i].regs[TEGRA_EMC_NUM_REGS - 1]); + + return 0; +} + +static int __devinit tegra_emc_probe(struct platform_device *pdev) +{ + struct tegra_emc_pdata *pdata; + struct resource *res; + + if (!emc_enable) { + dev_err(&pdev->dev, "disabled per module parameter\n"); + return -ENODEV; + } + + pdata = pdev->dev.platform_data; - emc_readl(tegra_emc_table[i].regs[TEGRA_EMC_NUM_REGS - 1]); + 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"); + return -ENOMEM; + } + + emc_regbase = devm_request_and_ioremap(&pdev->dev, res); + if (!emc_regbase) { + dev_err(&pdev->dev, "failed to remap registers\n"); + return -ENOMEM; + } + emc_pdev = pdev; return 0; } -void tegra_init_emc(const struct tegra_emc_table *table, int table_size) +static struct platform_driver tegra_emc_driver = { + .driver = { + .name = "tegra-emc", + .owner = THIS_MODULE, + }, + .probe = tegra_emc_probe, +}; + +static int __init tegra_emc_init(void) { - tegra_emc_table = table; - tegra_emc_table_size = table_size; + return platform_driver_register(&tegra_emc_driver); } +device_initcall(tegra_emc_init); diff --git a/arch/arm/mach-tegra/tegra2_emc.h b/arch/arm/mach-tegra/tegra2_emc.h index 19f08cb..f61409b 100644 --- a/arch/arm/mach-tegra/tegra2_emc.h +++ b/arch/arm/mach-tegra/tegra2_emc.h @@ -15,13 +15,10 @@ * */ -#define TEGRA_EMC_NUM_REGS 46 - -struct tegra_emc_table { - unsigned long rate; - u32 regs[TEGRA_EMC_NUM_REGS]; -}; +#ifndef __MACH_TEGRA_TEGRA2_EMC_H_ +#define __MACH_TEGRA_TEGRA2_EMC_H int tegra_emc_set_rate(unsigned long rate); long tegra_emc_round_rate(unsigned long rate); -void tegra_init_emc(const struct tegra_emc_table *table, int table_size); + +#endif |