From cd52c2a4b5c43631e429d06dce12e08b0cab477f Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Mon, 30 Mar 2015 10:59:52 +0100 Subject: clk: add support for clocks provided by SCP(System Control Processor) On some ARM based systems, a separate Cortex-M based System Control Processor(SCP) provides the overall power, clock, reset and system control. System Control and Power Interface(SCPI) Message Protocol is defined for the communication between the Application Cores(AP) and the SCP. This patch adds support for the clocks provided by SCP using SCPI protocol. Signed-off-by: Sudeep Holla Reviewed-by: Stephen Boyd Cc: Mike Turquette Cc: Liviu Dudau Cc: Lorenzo Pieralisi Cc: Jon Medhurst (Tixy) Cc: linux-clk@vger.kernel.org --- drivers/clk/Kconfig | 10 ++ drivers/clk/Makefile | 1 + drivers/clk/clk-scpi.c | 312 +++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 323 insertions(+) create mode 100644 drivers/clk/clk-scpi.c (limited to 'drivers/clk') diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig index 42f7120ca9ce..4aec54b90331 100644 --- a/drivers/clk/Kconfig +++ b/drivers/clk/Kconfig @@ -59,6 +59,16 @@ config COMMON_CLK_RK808 clocked at 32KHz each. Clkout1 is always on, Clkout2 can off by control register. +config COMMON_CLK_SCPI + tristate "Clock driver controlled via SCPI interface" + depends on ARM_SCPI_PROTOCOL || COMPILE_TEST + ---help--- + This driver provides support for clocks that are controlled + by firmware that implements the SCPI interface. + + This driver uses SCPI Message Protocol to interact with the + firmware providing all the clock controls. + config COMMON_CLK_SI5351 tristate "Clock driver for SiLabs 5351A/B/C" depends on I2C diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile index d08b3e5985be..a381431bd950 100644 --- a/drivers/clk/Makefile +++ b/drivers/clk/Makefile @@ -36,6 +36,7 @@ obj-$(CONFIG_COMMON_CLK_PALMAS) += clk-palmas.o obj-$(CONFIG_CLK_QORIQ) += clk-qoriq.o obj-$(CONFIG_COMMON_CLK_RK808) += clk-rk808.o obj-$(CONFIG_COMMON_CLK_S2MPS11) += clk-s2mps11.o +obj-$(CONFIG_COMMON_CLK_SCPI) += clk-scpi.o obj-$(CONFIG_COMMON_CLK_SI5351) += clk-si5351.o obj-$(CONFIG_COMMON_CLK_SI570) += clk-si570.o obj-$(CONFIG_COMMON_CLK_CDCE925) += clk-cdce925.o diff --git a/drivers/clk/clk-scpi.c b/drivers/clk/clk-scpi.c new file mode 100644 index 000000000000..72f0486b5de6 --- /dev/null +++ b/drivers/clk/clk-scpi.c @@ -0,0 +1,312 @@ +/* + * System Control and Power Interface (SCPI) Protocol based clock driver + * + * Copyright (C) 2015 ARM Ltd. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see . + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +struct scpi_clk { + u32 id; + struct clk_hw hw; + struct scpi_dvfs_info *info; + struct scpi_ops *scpi_ops; +}; + +#define to_scpi_clk(clk) container_of(clk, struct scpi_clk, hw) + +static unsigned long scpi_clk_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct scpi_clk *clk = to_scpi_clk(hw); + + return clk->scpi_ops->clk_get_val(clk->id); +} + +static long scpi_clk_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + /* + * We can't figure out what rate it will be, so just return the + * rate back to the caller. scpi_clk_recalc_rate() will be called + * after the rate is set and we'll know what rate the clock is + * running at then. + */ + return rate; +} + +static int scpi_clk_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct scpi_clk *clk = to_scpi_clk(hw); + + return clk->scpi_ops->clk_set_val(clk->id, rate); +} + +static const struct clk_ops scpi_clk_ops = { + .recalc_rate = scpi_clk_recalc_rate, + .round_rate = scpi_clk_round_rate, + .set_rate = scpi_clk_set_rate, +}; + +/* find closest match to given frequency in OPP table */ +static int __scpi_dvfs_round_rate(struct scpi_clk *clk, unsigned long rate) +{ + int idx; + u32 fmin = 0, fmax = ~0, ftmp; + const struct scpi_opp *opp = clk->info->opps; + + for (idx = 0; idx < clk->info->count; idx++, opp++) { + ftmp = opp->freq; + if (ftmp >= (u32)rate) { + if (ftmp <= fmax) + fmax = ftmp; + break; + } else if (ftmp >= fmin) { + fmin = ftmp; + } + } + return fmax != ~0 ? fmax : fmin; +} + +static unsigned long scpi_dvfs_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct scpi_clk *clk = to_scpi_clk(hw); + int idx = clk->scpi_ops->dvfs_get_idx(clk->id); + const struct scpi_opp *opp; + + if (idx < 0) + return 0; + + opp = clk->info->opps + idx; + return opp->freq; +} + +static long scpi_dvfs_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + struct scpi_clk *clk = to_scpi_clk(hw); + + return __scpi_dvfs_round_rate(clk, rate); +} + +static int __scpi_find_dvfs_index(struct scpi_clk *clk, unsigned long rate) +{ + int idx, max_opp = clk->info->count; + const struct scpi_opp *opp = clk->info->opps; + + for (idx = 0; idx < max_opp; idx++, opp++) + if (opp->freq == rate) + return idx; + return -EINVAL; +} + +static int scpi_dvfs_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct scpi_clk *clk = to_scpi_clk(hw); + int ret = __scpi_find_dvfs_index(clk, rate); + + if (ret < 0) + return ret; + return clk->scpi_ops->dvfs_set_idx(clk->id, (u8)ret); +} + +static const struct clk_ops scpi_dvfs_ops = { + .recalc_rate = scpi_dvfs_recalc_rate, + .round_rate = scpi_dvfs_round_rate, + .set_rate = scpi_dvfs_set_rate, +}; + +static const struct of_device_id scpi_clk_match[] = { + { .compatible = "arm,scpi-dvfs-clocks", .data = &scpi_dvfs_ops, }, + { .compatible = "arm,scpi-variable-clocks", .data = &scpi_clk_ops, }, + {} +}; + +static struct clk * +scpi_clk_ops_init(struct device *dev, const struct of_device_id *match, + struct scpi_clk *sclk, const char *name) +{ + struct clk_init_data init; + struct clk *clk; + unsigned long min = 0, max = 0; + + init.name = name; + init.flags = CLK_IS_ROOT; + init.num_parents = 0; + init.ops = match->data; + sclk->hw.init = &init; + sclk->scpi_ops = get_scpi_ops(); + + if (init.ops == &scpi_dvfs_ops) { + sclk->info = sclk->scpi_ops->dvfs_get_info(sclk->id); + if (IS_ERR(sclk->info)) + return NULL; + } else if (init.ops == &scpi_clk_ops) { + if (sclk->scpi_ops->clk_get_range(sclk->id, &min, &max) || !max) + return NULL; + } else { + return NULL; + } + + clk = devm_clk_register(dev, &sclk->hw); + if (!IS_ERR(clk) && max) + clk_hw_set_rate_range(&sclk->hw, min, max); + return clk; +} + +struct scpi_clk_data { + struct scpi_clk **clk; + unsigned int clk_num; +}; + +static struct clk * +scpi_of_clk_src_get(struct of_phandle_args *clkspec, void *data) +{ + struct scpi_clk *sclk; + struct scpi_clk_data *clk_data = data; + unsigned int idx = clkspec->args[0], count; + + for (count = 0; count < clk_data->clk_num; count++) { + sclk = clk_data->clk[count]; + if (idx == sclk->id) + return sclk->hw.clk; + } + + return ERR_PTR(-EINVAL); +} + +static int scpi_clk_add(struct device *dev, struct device_node *np, + const struct of_device_id *match) +{ + struct clk **clks; + int idx, count; + struct scpi_clk_data *clk_data; + + count = of_property_count_strings(np, "clock-output-names"); + if (count < 0) { + dev_err(dev, "%s: invalid clock output count\n", np->name); + return -EINVAL; + } + + clk_data = devm_kmalloc(dev, sizeof(*clk_data), GFP_KERNEL); + if (!clk_data) + return -ENOMEM; + + clk_data->clk_num = count; + clk_data->clk = devm_kcalloc(dev, count, sizeof(*clk_data->clk), + GFP_KERNEL); + if (!clk_data->clk) + return -ENOMEM; + + clks = devm_kcalloc(dev, count, sizeof(*clks), GFP_KERNEL); + if (!clks) + return -ENOMEM; + + for (idx = 0; idx < count; idx++) { + struct scpi_clk *sclk; + const char *name; + u32 val; + + sclk = devm_kzalloc(dev, sizeof(*sclk), GFP_KERNEL); + if (!sclk) + return -ENOMEM; + + if (of_property_read_string_index(np, "clock-output-names", + idx, &name)) { + dev_err(dev, "invalid clock name @ %s\n", np->name); + return -EINVAL; + } + + if (of_property_read_u32_index(np, "clock-indices", + idx, &val)) { + dev_err(dev, "invalid clock index @ %s\n", np->name); + return -EINVAL; + } + + sclk->id = val; + + clks[idx] = scpi_clk_ops_init(dev, match, sclk, name); + if (IS_ERR_OR_NULL(clks[idx])) + dev_err(dev, "failed to register clock '%s'\n", name); + else + dev_dbg(dev, "Registered clock '%s'\n", name); + clk_data->clk[idx] = sclk; + } + + return of_clk_add_provider(np, scpi_of_clk_src_get, clk_data); +} + +static int scpi_clocks_remove(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *child, *np = dev->of_node; + + for_each_available_child_of_node(np, child) + of_clk_del_provider(np); + return 0; +} + +static int scpi_clocks_probe(struct platform_device *pdev) +{ + int ret; + struct device *dev = &pdev->dev; + struct device_node *child, *np = dev->of_node; + const struct of_device_id *match; + + if (!get_scpi_ops()) + return -ENXIO; + + for_each_available_child_of_node(np, child) { + match = of_match_node(scpi_clk_match, child); + if (!match) + continue; + ret = scpi_clk_add(dev, child, match); + if (ret) { + scpi_clocks_remove(pdev); + return ret; + } + } + return 0; +} + +static const struct of_device_id scpi_clocks_ids[] = { + { .compatible = "arm,scpi-clocks", }, + {} +}; +MODULE_DEVICE_TABLE(of, scpi_clocks_ids); + +static struct platform_driver scpi_clocks_driver = { + .driver = { + .name = "scpi_clocks", + .of_match_table = scpi_clocks_ids, + }, + .probe = scpi_clocks_probe, + .remove = scpi_clocks_remove, +}; +module_platform_driver(scpi_clocks_driver); + +MODULE_AUTHOR("Sudeep Holla "); +MODULE_DESCRIPTION("ARM SCPI clock driver"); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.3 From 9490f01e247169a93262054074409ad73d71c4da Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Mon, 30 Mar 2015 10:59:52 +0100 Subject: clk: scpi: add support for cpufreq virtual device The clocks for the CPUs are provided by SCP and are managed by this clock driver. So the cpufreq device needs to be added only after the clock get registered and removed when this driver is unloaded. This patch manages the cpufreq virtual device based on the clock availability. Signed-off-by: Sudeep Holla Acked-by: Stephen Boyd Cc: Mike Turquette Cc: Liviu Dudau Cc: Lorenzo Pieralisi Cc: Jon Medhurst (Tixy) Cc: linux-clk@vger.kernel.org --- drivers/clk/clk-scpi.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'drivers/clk') diff --git a/drivers/clk/clk-scpi.c b/drivers/clk/clk-scpi.c index 72f0486b5de6..0b501a9fef92 100644 --- a/drivers/clk/clk-scpi.c +++ b/drivers/clk/clk-scpi.c @@ -34,6 +34,8 @@ struct scpi_clk { #define to_scpi_clk(clk) container_of(clk, struct scpi_clk, hw) +static struct platform_device *cpufreq_dev; + static unsigned long scpi_clk_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) { @@ -263,6 +265,11 @@ static int scpi_clocks_remove(struct platform_device *pdev) struct device *dev = &pdev->dev; struct device_node *child, *np = dev->of_node; + if (cpufreq_dev) { + platform_device_unregister(cpufreq_dev); + cpufreq_dev = NULL; + } + for_each_available_child_of_node(np, child) of_clk_del_provider(np); return 0; @@ -288,6 +295,12 @@ static int scpi_clocks_probe(struct platform_device *pdev) return ret; } } + /* Add the virtual cpufreq device */ + cpufreq_dev = platform_device_register_simple("scpi-cpufreq", + -1, NULL, 0); + if (!cpufreq_dev) + pr_warn("unable to register cpufreq device"); + return 0; } -- cgit v1.2.3 From 515f1a2027006839c08c842da919abfcc3c7ae2a Mon Sep 17 00:00:00 2001 From: Antoine Tenart Date: Thu, 15 Oct 2015 20:55:55 +0200 Subject: clk: berlin: add cpuclk Add cpuclk in the Berlin BG2Q clock driver. This clk has a divider fixed to 1. Signed-off-by: Antoine Tenart Acked-by: Stephen Boyd Signed-off-by: Sebastian Hesselbarth --- drivers/clk/berlin/bg2q.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'drivers/clk') diff --git a/drivers/clk/berlin/bg2q.c b/drivers/clk/berlin/bg2q.c index 221f40c2b850..72d2f3500db8 100644 --- a/drivers/clk/berlin/bg2q.c +++ b/drivers/clk/berlin/bg2q.c @@ -45,7 +45,7 @@ #define REG_SDIO0XIN_CLKCTL 0x0158 #define REG_SDIO1XIN_CLKCTL 0x015c -#define MAX_CLKS 27 +#define MAX_CLKS 28 static struct clk *clks[MAX_CLKS]; static struct clk_onecell_data clk_data; static DEFINE_SPINLOCK(lock); @@ -356,13 +356,13 @@ static void __init berlin2q_clock_setup(struct device_node *np) gd->bit_idx, 0, &lock); } - /* - * twdclk is derived from cpu/3 - * TODO: use cpupll until cpuclk is not available - */ + /* cpuclk divider is fixed to 1 */ + clks[CLKID_CPU] = + clk_register_fixed_factor(NULL, "cpu", clk_names[CPUPLL], + 0, 1, 1); + /* twdclk is derived from cpu/3 */ clks[CLKID_TWD] = - clk_register_fixed_factor(NULL, "twd", clk_names[CPUPLL], - 0, 1, 3); + clk_register_fixed_factor(NULL, "twd", "cpu", 0, 1, 3); /* check for errors on leaf clocks */ for (n = 0; n < MAX_CLKS; n++) { -- cgit v1.2.3