This patch adds modularization support to the Tegra124 EMC driver. Driver now can be compiled as a loadable kernel module.
Signed-off-by: Dmitry Osipenko digetx@gmail.com --- drivers/clk/tegra/clk-tegra124-emc.c | 63 +++++++++++++++++----------- drivers/clk/tegra/clk-tegra124.c | 3 +- drivers/clk/tegra/clk.h | 12 ------ drivers/memory/tegra/Kconfig | 2 +- drivers/memory/tegra/tegra124-emc.c | 32 +++++++++----- include/linux/clk/tegra.h | 11 +++++ include/soc/tegra/emc.h | 16 ------- 7 files changed, 73 insertions(+), 66 deletions(-) delete mode 100644 include/soc/tegra/emc.h
diff --git a/drivers/clk/tegra/clk-tegra124-emc.c b/drivers/clk/tegra/clk-tegra124-emc.c index 745f9faa98d8..4d8b8f1ba7cd 100644 --- a/drivers/clk/tegra/clk-tegra124-emc.c +++ b/drivers/clk/tegra/clk-tegra124-emc.c @@ -11,7 +11,9 @@ #include <linux/clk-provider.h> #include <linux/clk.h> #include <linux/clkdev.h> +#include <linux/clk/tegra.h> #include <linux/delay.h> +#include <linux/export.h> #include <linux/io.h> #include <linux/module.h> #include <linux/of_address.h> @@ -21,10 +23,10 @@ #include <linux/string.h>
#include <soc/tegra/fuse.h> -#include <soc/tegra/emc.h>
#include "clk.h"
+#define CLK_BASE 0x60006000 #define CLK_SOURCE_EMC 0x19c
#define CLK_SOURCE_EMC_EMC_2X_CLK_DIVISOR_SHIFT 0 @@ -79,7 +81,9 @@ struct tegra_clk_emc {
int num_timings; struct emc_timing *timings; - spinlock_t *lock; + + tegra124_emc_prepare_timing_change_cb *prepare_timing_change; + tegra124_emc_complete_timing_change_cb *complete_timing_change; };
/* Common clock framework callback implementations */ @@ -98,7 +102,7 @@ static unsigned long emc_recalc_rate(struct clk_hw *hw, */ parent_rate = clk_hw_get_rate(clk_hw_get_parent(hw));
- val = readl(tegra->clk_regs + CLK_SOURCE_EMC); + val = readl(tegra->clk_regs); div = val & CLK_SOURCE_EMC_EMC_2X_CLK_DIVISOR_MASK;
return parent_rate / (div + 2) * 2; @@ -163,7 +167,7 @@ static u8 emc_get_parent(struct clk_hw *hw)
tegra = container_of(hw, struct tegra_clk_emc, hw);
- val = readl(tegra->clk_regs + CLK_SOURCE_EMC); + val = readl(tegra->clk_regs);
return (val >> CLK_SOURCE_EMC_EMC_2X_CLK_SRC_SHIFT) & CLK_SOURCE_EMC_EMC_2X_CLK_SRC_MASK; @@ -204,7 +208,6 @@ static int emc_set_timing(struct tegra_clk_emc *tegra, int err; u8 div; u32 car_value; - unsigned long flags = 0; struct tegra_emc *emc = emc_ensure_emc_driver(tegra);
if (!emc) @@ -241,13 +244,11 @@ static int emc_set_timing(struct tegra_clk_emc *tegra,
div = timing->parent_rate / (timing->rate / 2) - 2;
- err = tegra_emc_prepare_timing_change(emc, timing->rate); + err = tegra->prepare_timing_change(emc, timing->rate); if (err) return err;
- spin_lock_irqsave(tegra->lock, flags); - - car_value = readl(tegra->clk_regs + CLK_SOURCE_EMC); + car_value = readl(tegra->clk_regs);
car_value &= ~CLK_SOURCE_EMC_EMC_2X_CLK_SRC(~0); car_value |= CLK_SOURCE_EMC_EMC_2X_CLK_SRC(timing->parent_index); @@ -255,11 +256,9 @@ static int emc_set_timing(struct tegra_clk_emc *tegra, car_value &= ~CLK_SOURCE_EMC_EMC_2X_CLK_DIVISOR(~0); car_value |= CLK_SOURCE_EMC_EMC_2X_CLK_DIVISOR(div);
- writel(car_value, tegra->clk_regs + CLK_SOURCE_EMC); - - spin_unlock_irqrestore(tegra->lock, flags); + writel(car_value, tegra->clk_regs);
- tegra_emc_complete_timing_change(emc, timing->rate); + tegra->complete_timing_change(emc, timing->rate);
clk_hw_reparent(&tegra->hw, __clk_get_hw(timing->parent)); clk_disable_unprepare(tegra->prev_parent); @@ -473,12 +472,15 @@ static const struct clk_ops tegra_clk_emc_ops = { .get_parent = emc_get_parent, };
-struct clk *tegra_clk_register_emc(void __iomem *base, struct device_node *np, - spinlock_t *lock) +struct clk * +tegra124_clk_register_emc(struct device_node *emc_np, + tegra124_emc_prepare_timing_change_cb *prep_cb, + tegra124_emc_complete_timing_change_cb *complete_cb) { struct tegra_clk_emc *tegra; struct clk_init_data init; struct device_node *node; + struct resource res; u32 node_ram_code; struct clk *clk; int err; @@ -487,12 +489,21 @@ struct clk *tegra_clk_register_emc(void __iomem *base, struct device_node *np, if (!tegra) return ERR_PTR(-ENOMEM);
- tegra->clk_regs = base; - tegra->lock = lock; + res.start = CLK_BASE + CLK_SOURCE_EMC; + res.end = res.start + 3; + res.flags = IORESOURCE_MEM;
- tegra->num_timings = 0; + tegra->clk_regs = ioremap(res.start, resource_size(&res)); + if (!tegra->clk_regs) { + pr_err("failed to map CLK_SOURCE_EMC\n"); + return ERR_PTR(-EINVAL); + } + + tegra->emc_node = emc_np; + tegra->prepare_timing_change = prep_cb; + tegra->complete_timing_change = complete_cb;
- for_each_child_of_node(np, node) { + for_each_child_of_node(emc_np, node) { err = of_property_read_u32(node, "nvidia,ram-code", &node_ram_code); if (err) @@ -512,11 +523,6 @@ struct clk *tegra_clk_register_emc(void __iomem *base, struct device_node *np, if (tegra->num_timings == 0) pr_warn("%s: no memory timings registered\n", __func__);
- tegra->emc_node = of_parse_phandle(np, - "nvidia,external-memory-controller", 0); - if (!tegra->emc_node) - pr_warn("%s: couldn't find node for EMC driver\n", __func__); - init.name = "emc"; init.ops = &tegra_clk_emc_ops; init.flags = CLK_IS_CRITICAL; @@ -536,5 +542,12 @@ struct clk *tegra_clk_register_emc(void __iomem *base, struct device_node *np, /* Allow debugging tools to see the EMC clock */ clk_register_clkdev(clk, "emc", "tegra-clk-debug");
+ /* + * Don't allow the kernel module to be unloaded, unloading is not + * supported by the EMC driver. + */ + try_module_get(THIS_MODULE); + return clk; -}; +} +EXPORT_SYMBOL_GPL(tegra124_clk_register_emc); diff --git a/drivers/clk/tegra/clk-tegra124.c b/drivers/clk/tegra/clk-tegra124.c index 0c956e14b9ca..228d87367ac6 100644 --- a/drivers/clk/tegra/clk-tegra124.c +++ b/drivers/clk/tegra/clk-tegra124.c @@ -928,6 +928,7 @@ static struct tegra_clk tegra124_clks[tegra_clk_max] __initdata = { [tegra_clk_audio4_mux] = { .dt_id = TEGRA124_CLK_AUDIO4_MUX, .present = true }, [tegra_clk_spdif_mux] = { .dt_id = TEGRA124_CLK_SPDIF_MUX, .present = true }, [tegra_clk_cec] = { .dt_id = TEGRA124_CLK_CEC, .present = true }, + [tegra_clk_emc] = { .dt_id = TEGRA124_CLK_EMC, .present = false }, };
static struct tegra_devclk devclks[] __initdata = { @@ -1516,8 +1517,6 @@ static void __init tegra124_132_clock_init_post(struct device_node *np) tegra124_reset_deassert); tegra_add_of_provider(np, of_clk_src_onecell_get);
- clks[TEGRA124_CLK_EMC] = tegra_clk_register_emc(clk_base, np, NULL); - tegra_register_devclks(devclks, ARRAY_SIZE(devclks));
tegra_cpu_car_ops = &tegra124_cpu_car_ops; diff --git a/drivers/clk/tegra/clk.h b/drivers/clk/tegra/clk.h index 5ed8b95d331c..11a8bbe650c5 100644 --- a/drivers/clk/tegra/clk.h +++ b/drivers/clk/tegra/clk.h @@ -881,18 +881,6 @@ void tegra_super_clk_gen5_init(void __iomem *clk_base, void __iomem *pmc_base, struct tegra_clk *tegra_clks, struct tegra_clk_pll_params *pll_params);
-#ifdef CONFIG_TEGRA124_EMC -struct clk *tegra_clk_register_emc(void __iomem *base, struct device_node *np, - spinlock_t *lock); -#else -static inline struct clk *tegra_clk_register_emc(void __iomem *base, - struct device_node *np, - spinlock_t *lock) -{ - return NULL; -} -#endif - void tegra114_clock_tune_cpu_trimmers_high(void); void tegra114_clock_tune_cpu_trimmers_low(void); void tegra114_clock_tune_cpu_trimmers_init(void); diff --git a/drivers/memory/tegra/Kconfig b/drivers/memory/tegra/Kconfig index bd453de9d446..c1cad4ce6251 100644 --- a/drivers/memory/tegra/Kconfig +++ b/drivers/memory/tegra/Kconfig @@ -28,7 +28,7 @@ config TEGRA30_EMC external memory.
config TEGRA124_EMC - bool "NVIDIA Tegra124 External Memory Controller driver" + tristate "NVIDIA Tegra124 External Memory Controller driver" default y depends on TEGRA_MC && ARCH_TEGRA_124_SOC help diff --git a/drivers/memory/tegra/tegra124-emc.c b/drivers/memory/tegra/tegra124-emc.c index d19fb7ae230d..98d98d09b00c 100644 --- a/drivers/memory/tegra/tegra124-emc.c +++ b/drivers/memory/tegra/tegra124-emc.c @@ -9,16 +9,17 @@ #include <linux/clk-provider.h> #include <linux/clk.h> #include <linux/clkdev.h> +#include <linux/clk/tegra.h> #include <linux/debugfs.h> #include <linux/delay.h> #include <linux/io.h> +#include <linux/module.h> #include <linux/of_address.h> #include <linux/of_platform.h> #include <linux/platform_device.h> #include <linux/sort.h> #include <linux/string.h>
-#include <soc/tegra/emc.h> #include <soc/tegra/fuse.h> #include <soc/tegra/mc.h>
@@ -562,8 +563,8 @@ static struct emc_timing *tegra_emc_find_timing(struct tegra_emc *emc, return timing; }
-int tegra_emc_prepare_timing_change(struct tegra_emc *emc, - unsigned long rate) +static int tegra_emc_prepare_timing_change(struct tegra_emc *emc, + unsigned long rate) { struct emc_timing *timing = tegra_emc_find_timing(emc, rate); struct emc_timing *last = &emc->last_timing; @@ -790,8 +791,8 @@ int tegra_emc_prepare_timing_change(struct tegra_emc *emc, return 0; }
-void tegra_emc_complete_timing_change(struct tegra_emc *emc, - unsigned long rate) +static void tegra_emc_complete_timing_change(struct tegra_emc *emc, + unsigned long rate) { struct emc_timing *timing = tegra_emc_find_timing(emc, rate); struct emc_timing *last = &emc->last_timing; @@ -986,6 +987,7 @@ static const struct of_device_id tegra_emc_of_match[] = { { .compatible = "nvidia,tegra124-emc" }, {} }; +MODULE_DEVICE_TABLE(of, tegra_emc_of_match);
static struct device_node * tegra_emc_find_node_by_ram_code(struct device_node *node, u32 ram_code) @@ -1251,9 +1253,20 @@ static int tegra_emc_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, emc);
+ tegra124_clk_register_emc(pdev->dev.of_node, + tegra_emc_prepare_timing_change, + tegra_emc_complete_timing_change); + if (IS_ENABLED(CONFIG_DEBUG_FS)) emc_debugfs_init(&pdev->dev, emc);
+ /* + * Don't allow the kernel module to be unloaded. Unloading adds some + * extra complexity which doesn't really worth the effort in a case of + * this driver. + */ + try_module_get(THIS_MODULE); + return 0; };
@@ -1265,9 +1278,8 @@ static struct platform_driver tegra_emc_driver = { .suppress_bind_attrs = true, }, }; +module_platform_driver(tegra_emc_driver);
-static int tegra_emc_init(void) -{ - return platform_driver_register(&tegra_emc_driver); -} -subsys_initcall(tegra_emc_init); +MODULE_AUTHOR("Mikko Perttunen mperttunen@nvidia.com"); +MODULE_DESCRIPTION("NVIDIA Tegra124 EMC driver"); +MODULE_LICENSE("GPL v2"); diff --git a/include/linux/clk/tegra.h b/include/linux/clk/tegra.h index 3f01d43f0598..797b8bde18de 100644 --- a/include/linux/clk/tegra.h +++ b/include/linux/clk/tegra.h @@ -136,6 +136,8 @@ extern void tegra210_clk_emc_dll_update_setting(u32 emc_dll_src_value); extern void tegra210_clk_emc_update_setting(u32 emc_src_value);
struct clk; +struct device_node; +struct tegra_emc;
typedef long (tegra20_clk_emc_round_cb)(unsigned long rate, unsigned long min_rate, @@ -146,6 +148,15 @@ void tegra20_clk_set_emc_round_callback(tegra20_clk_emc_round_cb *round_cb, void *cb_arg); int tegra20_clk_prepare_emc_mc_same_freq(struct clk *emc_clk, bool same);
+typedef int (tegra124_emc_prepare_timing_change_cb)(struct tegra_emc *emc, + unsigned long rate); +typedef void (tegra124_emc_complete_timing_change_cb)(struct tegra_emc *emc, + unsigned long rate); +struct clk * +tegra124_clk_register_emc(struct device_node *emc_np, + tegra124_emc_prepare_timing_change_cb *prep_cb, + tegra124_emc_complete_timing_change_cb *complete_cb); + struct tegra210_clk_emc_config { unsigned long rate; bool same_freq; diff --git a/include/soc/tegra/emc.h b/include/soc/tegra/emc.h deleted file mode 100644 index 05199a97ccf4..000000000000 --- a/include/soc/tegra/emc.h +++ /dev/null @@ -1,16 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0-only */ -/* - * Copyright (c) 2014 NVIDIA Corporation. All rights reserved. - */ - -#ifndef __SOC_TEGRA_EMC_H__ -#define __SOC_TEGRA_EMC_H__ - -struct tegra_emc; - -int tegra_emc_prepare_timing_change(struct tegra_emc *emc, - unsigned long rate); -void tegra_emc_complete_timing_change(struct tegra_emc *emc, - unsigned long rate); - -#endif /* __SOC_TEGRA_EMC_H__ */