Add RZ/G2L MTU3 counter driver. Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx> --- v1->v3: * Modelled as a counter device supporting 3 counters(2 16-bit and 32-bit) * Add kernel-doc comments to document struct rz_mtu3_cnt * Removed mmio variable from struct rz_mtu3_cnt * Removed cnt local variable from rz_mtu3_count_read() * Replaced -EINVAL->-ERANGE for out of range error conditions. * Removed explicit cast from write functions. * Removed local variable val from rz_mtu3_count_ceiling_read() * Added lock for RMW for counter/ceiling updates. * Added different synapses for counter0 and counter{1,2} * Used ARRAY for assigning num_counts. * Added PM runtime for managing clocks. * Add MODULE_IMPORT_NS(COUNTER) to import the COUNTER namespace. --- drivers/counter/Kconfig | 9 + drivers/counter/Makefile | 1 + drivers/counter/rz-mtu3-cnt.c | 568 ++++++++++++++++++++++++++++++++++ 3 files changed, 578 insertions(+) create mode 100644 drivers/counter/rz-mtu3-cnt.c diff --git a/drivers/counter/Kconfig b/drivers/counter/Kconfig index d388bf26f4dc..531b187e4630 100644 --- a/drivers/counter/Kconfig +++ b/drivers/counter/Kconfig @@ -39,6 +39,15 @@ config INTERRUPT_CNT To compile this driver as a module, choose M here: the module will be called interrupt-cnt. +config RZ_MTU3_CNT + tristate "RZ/G2L MTU3 counter driver" + depends on MFD_RZ_MTU3 || COMPILE_TEST + help + Select this option to enable RZ/G2L MTU3 counter driver. + + To compile this driver as a module, choose M here: the + module will be called rz-mtu3-cnt. + config STM32_TIMER_CNT tristate "STM32 Timer encoder counter driver" depends on MFD_STM32_TIMERS || COMPILE_TEST diff --git a/drivers/counter/Makefile b/drivers/counter/Makefile index b9a369e0d4fc..933fdd50b3e4 100644 --- a/drivers/counter/Makefile +++ b/drivers/counter/Makefile @@ -8,6 +8,7 @@ counter-y := counter-core.o counter-sysfs.o counter-chrdev.o obj-$(CONFIG_104_QUAD_8) += 104-quad-8.o obj-$(CONFIG_INTERRUPT_CNT) += interrupt-cnt.o +obj-$(CONFIG_RZ_MTU3_CNT) += rz-mtu3-cnt.o obj-$(CONFIG_STM32_TIMER_CNT) += stm32-timer-cnt.o obj-$(CONFIG_STM32_LPTIMER_CNT) += stm32-lptimer-cnt.o obj-$(CONFIG_TI_EQEP) += ti-eqep.o diff --git a/drivers/counter/rz-mtu3-cnt.c b/drivers/counter/rz-mtu3-cnt.c new file mode 100644 index 000000000000..26b5ea3852f8 --- /dev/null +++ b/drivers/counter/rz-mtu3-cnt.c @@ -0,0 +1,568 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Renesas RZ/G2L MTU3a Counter driver + * + * Copyright (C) 2022 Renesas Electronics Corporation + */ +#include <linux/counter.h> +#include <linux/mfd/rz-mtu3.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/types.h> + +#define RZ_MTU3_TSR_TCFD BIT(7) +#define RZ_MTU3_MAX_HW_CNTR_CHANNELS (2) + +#define RZ_MTU3_TMDR1_PH_CNT_MODE_1 (4) +#define RZ_MTU3_TMDR1_PH_CNT_MODE_2 (5) +#define RZ_MTU3_TMDR1_PH_CNT_MODE_3 (6) +#define RZ_MTU3_TMDR1_PH_CNT_MODE_4 (7) +#define RZ_MTU3_TMDR1_PH_CNT_MODE_5 (9) +#define RZ_MTU3_TMDR1_PH_CNT_MODE_MASK (0xf) + +#define RZ_MTU3_TCR_CCLR GENMASK(7, 5) +#define RZ_MTU3_TCR_CCLR_NONE FIELD_PREP(RZ_MTU3_TCR_CCLR, 0) + +#define RZ_MTU3_TMDR3_LWA BIT(0) +#define RZ_MTU3_32_BIT_CH (2) + +#define RZ_MTU3_TIOR_IC_BOTH (10) + +/** + * struct rz_mtu3_cnt - MTU3 counter private data + * + * @clk: MTU3 module clock + * @lock: Lock to prevent concurrent access for ceiling and count + * @rz_mtu3_channel: HW channels for the counters + */ +struct rz_mtu3_cnt { + struct clk *clk; + struct mutex lock; + struct rz_mtu3_channel *ch[RZ_MTU3_MAX_HW_CNTR_CHANNELS]; +}; + +static const enum counter_function rz_mtu3_count_functions[] = { + COUNTER_FUNCTION_QUADRATURE_X4, + COUNTER_FUNCTION_PULSE_DIRECTION, + COUNTER_FUNCTION_QUADRATURE_X2_B, +}; + +static bool rz_mtu3_is_16_bit_cnt_mode(struct rz_mtu3_cnt *const priv) +{ + return (priv->ch[0]->function == RZ_MTU3_16BIT_PHASE_COUNTING || + priv->ch[1]->function == RZ_MTU3_16BIT_PHASE_COUNTING); +} + +static bool rz_mtu3_is_32_bit_cnt_mode(struct rz_mtu3_cnt *const priv) +{ + return (priv->ch[0]->function == RZ_MTU3_32BIT_PHASE_COUNTING && + priv->ch[1]->function == RZ_MTU3_32BIT_PHASE_COUNTING); +} + +static int rz_mtu3_count_read(struct counter_device *counter, + struct counter_count *count, u64 *val) +{ + struct rz_mtu3_cnt *const priv = counter_priv(counter); + u32 id = count->id & 1; + + if (count->id == RZ_MTU3_32_BIT_CH) + *val = rz_mtu3_32bit_ch_read(priv->ch[id], RZ_MTU3_TCNTLW); + else + *val = rz_mtu3_16bit_ch_read(priv->ch[id], RZ_MTU3_TCNT); + + return 0; +} + +static int rz_mtu3_count_write(struct counter_device *counter, + struct counter_count *count, const u64 val) +{ + struct rz_mtu3_cnt *const priv = counter_priv(counter); + u32 id = count->id & 1; + u32 ceiling; + + mutex_lock(&priv->lock); + if (count->id == RZ_MTU3_32_BIT_CH) + ceiling = rz_mtu3_32bit_ch_read(priv->ch[id], RZ_MTU3_TGRALW); + else + ceiling = rz_mtu3_16bit_ch_read(priv->ch[id], RZ_MTU3_TGRA); + + if (val > ceiling) { + mutex_unlock(&priv->lock); + return -ERANGE; + } + + if (count->id == RZ_MTU3_32_BIT_CH) + rz_mtu3_32bit_ch_write(priv->ch[id], RZ_MTU3_TCNTLW, val); + else + rz_mtu3_16bit_ch_write(priv->ch[id], RZ_MTU3_TCNT, val); + + mutex_unlock(&priv->lock); + + return 0; +} + +static int rz_mtu3_count_function_read(struct counter_device *counter, + struct counter_count *count, + enum counter_function *function) +{ + struct rz_mtu3_cnt *const priv = counter_priv(counter); + u32 id = count->id & 1; + u8 val; + + val = rz_mtu3_8bit_ch_read(priv->ch[id], RZ_MTU3_TMDR1); + + switch (val & RZ_MTU3_TMDR1_PH_CNT_MODE_MASK) { + case RZ_MTU3_TMDR1_PH_CNT_MODE_1: + *function = COUNTER_FUNCTION_QUADRATURE_X4; + break; + case RZ_MTU3_TMDR1_PH_CNT_MODE_2: + *function = COUNTER_FUNCTION_PULSE_DIRECTION; + break; + case RZ_MTU3_TMDR1_PH_CNT_MODE_4: + *function = COUNTER_FUNCTION_QUADRATURE_X2_B; + break; + default: + return -EINVAL; + } + + return 0; +} + +static int rz_mtu3_count_function_write(struct counter_device *counter, + struct counter_count *count, + enum counter_function function) +{ + struct rz_mtu3_cnt *const priv = counter_priv(counter); + u32 id = count->id & 1; + u8 mode; + + switch (function) { + case COUNTER_FUNCTION_QUADRATURE_X4: + mode = RZ_MTU3_TMDR1_PH_CNT_MODE_1; + break; + case COUNTER_FUNCTION_PULSE_DIRECTION: + mode = RZ_MTU3_TMDR1_PH_CNT_MODE_2; + break; + case COUNTER_FUNCTION_QUADRATURE_X2_B: + mode = RZ_MTU3_TMDR1_PH_CNT_MODE_4; + break; + default: + return -EINVAL; + } + + rz_mtu3_8bit_ch_write(priv->ch[id], RZ_MTU3_TMDR1, mode); + + return 0; +} + +static int rz_mtu3_count_direction_read(struct counter_device *counter, + struct counter_count *count, + enum counter_count_direction *direction) +{ + struct rz_mtu3_cnt *const priv = counter_priv(counter); + u32 id = count->id & 1; + u8 cnt; + + cnt = rz_mtu3_8bit_ch_read(priv->ch[id], RZ_MTU3_TSR); + + if (cnt & RZ_MTU3_TSR_TCFD) + *direction = COUNTER_COUNT_DIRECTION_FORWARD; + else + *direction = COUNTER_COUNT_DIRECTION_BACKWARD; + + return 0; +} + +static int rz_mtu3_count_ceiling_read(struct counter_device *counter, + struct counter_count *count, + u64 *ceiling) +{ + struct rz_mtu3_cnt *const priv = counter_priv(counter); + u32 id = count->id & 1; + + if (count->id == RZ_MTU3_32_BIT_CH) + *ceiling = rz_mtu3_32bit_ch_read(priv->ch[id], RZ_MTU3_TGRALW); + else + *ceiling = rz_mtu3_16bit_ch_read(priv->ch[id], RZ_MTU3_TGRA); + + return 0; +} + +static int rz_mtu3_count_ceiling_write(struct counter_device *counter, + struct counter_count *count, + u64 ceiling) +{ + struct rz_mtu3_cnt *const priv = counter_priv(counter); + u32 id = count->id & 1; + + if (ceiling > U16_MAX && rz_mtu3_is_16_bit_cnt_mode(priv)) + return -ERANGE; + + if (ceiling > U32_MAX && rz_mtu3_is_32_bit_cnt_mode(priv)) + return -ERANGE; + + mutex_lock(&priv->lock); + if (ceiling == 0) { + rz_mtu3_8bit_ch_write(priv->ch[id], RZ_MTU3_TCR, + RZ_MTU3_TCR_CCLR_NONE); + + } else { + if (count->id == RZ_MTU3_32_BIT_CH) + rz_mtu3_32bit_ch_write(priv->ch[id], RZ_MTU3_TGRALW, ceiling); + else + rz_mtu3_16bit_ch_write(priv->ch[id], RZ_MTU3_TGRA, ceiling); + + rz_mtu3_8bit_ch_write(priv->ch[id], RZ_MTU3_TCR, + RZ_MTU3_TCR_CCLR_TGRA); + } + mutex_unlock(&priv->lock); + + return 0; +} + +static void rz_mtu3_32bit_cnt_setting(struct counter_device *counter, int id) +{ + struct rz_mtu3_cnt *const priv = counter_priv(counter); + + /* + * 32-bit phase counting need MTU1 and MTU2 to create 32-bit cascade + * counter. + */ + priv->ch[0]->function = RZ_MTU3_32BIT_PHASE_COUNTING; + priv->ch[1]->function = RZ_MTU3_32BIT_PHASE_COUNTING; + + rz_mtu3_shared_reg_write(priv->ch[0], RZ_MTU3_TMDR3, RZ_MTU3_TMDR3_LWA); + + /* Phase counting mode 1 is used as default in initialization. */ + rz_mtu3_8bit_ch_write(priv->ch[0], RZ_MTU3_TMDR1, + RZ_MTU3_TMDR1_PH_CNT_MODE_1); + + rz_mtu3_8bit_ch_write(priv->ch[0], RZ_MTU3_TCR, RZ_MTU3_TCR_CCLR_TGRA); + rz_mtu3_8bit_ch_write(priv->ch[0], RZ_MTU3_TIOR, RZ_MTU3_TIOR_IC_BOTH); + + rz_mtu3_enable(priv->ch[0]); + rz_mtu3_enable(priv->ch[1]); +} + +static void rz_mtu3_16bit_cnt_setting(struct counter_device *counter, int id) +{ + struct rz_mtu3_cnt *const priv = counter_priv(counter); + + priv->ch[id]->function = RZ_MTU3_16BIT_PHASE_COUNTING; + + /* Phase counting mode 1 is used as default in initialization. */ + rz_mtu3_8bit_ch_write(priv->ch[id], RZ_MTU3_TMDR1, + RZ_MTU3_TMDR1_PH_CNT_MODE_1); + + rz_mtu3_8bit_ch_write(priv->ch[id], RZ_MTU3_TCR, RZ_MTU3_TCR_CCLR_TGRA); + rz_mtu3_16bit_ch_write(priv->ch[id], RZ_MTU3_TGRA, U16_MAX); + + rz_mtu3_enable(priv->ch[id]); +} + +static int rz_mtu3_initialize_counter(struct counter_device *counter, int id) +{ + struct rz_mtu3_cnt *const priv = counter_priv(counter); + + if (id == RZ_MTU3_32_BIT_CH && rz_mtu3_is_16_bit_cnt_mode(priv)) + return -EBUSY; + + if (id != RZ_MTU3_32_BIT_CH && rz_mtu3_is_32_bit_cnt_mode(priv)) + return -EBUSY; + + if (id == RZ_MTU3_32_BIT_CH) + rz_mtu3_32bit_cnt_setting(counter, id); + else + rz_mtu3_16bit_cnt_setting(counter, id); + + return 0; +} + +static void rz_mtu3_terminate_counter(struct counter_device *counter, int id) +{ + struct rz_mtu3_cnt *const priv = counter_priv(counter); + + if (id == RZ_MTU3_32_BIT_CH) { + priv->ch[0]->function = RZ_MTU3_NORMAL; + priv->ch[1]->function = RZ_MTU3_NORMAL; + rz_mtu3_shared_reg_write(priv->ch[0], RZ_MTU3_TMDR3, 0); + rz_mtu3_disable(priv->ch[1]); + rz_mtu3_disable(priv->ch[0]); + } else { + priv->ch[id]->function = RZ_MTU3_NORMAL; + rz_mtu3_disable(priv->ch[id]); + } +} + +static int rz_mtu3_count_enable_read(struct counter_device *counter, + struct counter_count *count, u8 *enable) +{ + struct rz_mtu3_cnt *const priv = counter_priv(counter); + + if (count->id == RZ_MTU3_32_BIT_CH) + *enable = rz_mtu3_is_enabled(priv->ch[0]) && + rz_mtu3_is_enabled(priv->ch[1]); + else + *enable = rz_mtu3_is_enabled(priv->ch[count->id]); + + return 0; +} + +static int rz_mtu3_count_enable_write(struct counter_device *counter, + struct counter_count *count, u8 enable) +{ + struct rz_mtu3_cnt *const priv = counter_priv(counter); + struct rz_mtu3_channel *ch = priv->ch[count->id & 0x1]; + int ret = 0; + + if (enable) { + pm_runtime_get_sync(ch->dev); + ret = rz_mtu3_initialize_counter(counter, count->id); + } else { + rz_mtu3_terminate_counter(counter, count->id); + pm_runtime_put(ch->dev); + } + + return ret; +} + +static struct counter_comp rz_mtu3_count_ext[] = { + COUNTER_COMP_DIRECTION(rz_mtu3_count_direction_read), + COUNTER_COMP_ENABLE(rz_mtu3_count_enable_read, + rz_mtu3_count_enable_write), + COUNTER_COMP_CEILING(rz_mtu3_count_ceiling_read, + rz_mtu3_count_ceiling_write), +}; + +static const enum counter_synapse_action rz_mtu3_synapse_actions[] = { + COUNTER_SYNAPSE_ACTION_BOTH_EDGES, + COUNTER_SYNAPSE_ACTION_RISING_EDGE, + COUNTER_SYNAPSE_ACTION_NONE, +}; + +static int rz_mtu3_action_read(struct counter_device *counter, + struct counter_count *count, + struct counter_synapse *synapse, + enum counter_synapse_action *action) +{ + const size_t signal_a_id = count->synapses[0].signal->id; + const size_t signal_b_id = count->synapses[1].signal->id; + enum counter_function function; + int err; + + err = rz_mtu3_count_function_read(counter, count, &function); + if (err) + return err; + + /* Default action mode */ + *action = COUNTER_SYNAPSE_ACTION_NONE; + + switch (function) { + case COUNTER_FUNCTION_PULSE_DIRECTION: + /* + * Rising edges on signal A updates the respective count. + * The input level of signal B determines direction. + */ + if (synapse->signal->id == signal_a_id) + *action = COUNTER_SYNAPSE_ACTION_RISING_EDGE; + break; + case COUNTER_FUNCTION_QUADRATURE_X2_B: + /* + * Any state transition on quadrature pair signal B updates + * the respective count. + */ + if (synapse->signal->id == signal_b_id) + *action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES; + break; + case COUNTER_FUNCTION_QUADRATURE_X4: + /* counts up/down on both edges of A and B signal*/ + *action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES; + break; + default: + return -EINVAL; + } + + return 0; +} + +static const struct counter_ops rz_mtu3_cnt_ops = { + .count_read = rz_mtu3_count_read, + .count_write = rz_mtu3_count_write, + .function_read = rz_mtu3_count_function_read, + .function_write = rz_mtu3_count_function_write, + .action_read = rz_mtu3_action_read, +}; + +#define RZ_MTU3_PHASE_SIGNAL(_id, _name) { \ + .id = (_id), \ + .name = (_name), \ +} + +static struct counter_signal rz_mtu3_signals[] = { + RZ_MTU3_PHASE_SIGNAL(0, "MTU1 MTCLKA"), + RZ_MTU3_PHASE_SIGNAL(1, "MTU1 MTCLKB"), + RZ_MTU3_PHASE_SIGNAL(2, "MTU2 MTCLKC"), + RZ_MTU3_PHASE_SIGNAL(3, "MTU2 MTCLKD"), +}; + +#define RZ_MTU3_COUNT_SYNAPSES(_id) { \ + { \ + .actions_list = rz_mtu3_synapse_actions, \ + .num_actions = ARRAY_SIZE(rz_mtu3_synapse_actions), \ + .signal = rz_mtu3_signals + 2 * (_id) \ + }, \ + { \ + .actions_list = rz_mtu3_synapse_actions, \ + .num_actions = ARRAY_SIZE(rz_mtu3_synapse_actions), \ + .signal = rz_mtu3_signals + 2 * (_id) + 1 \ + } \ +} + +static struct counter_synapse rz_mtu3_count_synapses[][2] = { + RZ_MTU3_COUNT_SYNAPSES(0), RZ_MTU3_COUNT_SYNAPSES(1) +}; + +static struct counter_count rz_mtu3_counts[] = { + { + .id = 0, + .name = "Channel 1 Count(16-bit)", + .functions_list = rz_mtu3_count_functions, + .num_functions = ARRAY_SIZE(rz_mtu3_count_functions), + .synapses = rz_mtu3_count_synapses[0], + .num_synapses = 2, + .ext = rz_mtu3_count_ext, + .num_ext = ARRAY_SIZE(rz_mtu3_count_ext), + }, + { + .id = 1, + .name = "Channel 2 Count(16-bit)", + .functions_list = rz_mtu3_count_functions, + .num_functions = ARRAY_SIZE(rz_mtu3_count_functions), + .synapses = rz_mtu3_count_synapses[0], + .num_synapses = 4, + .ext = rz_mtu3_count_ext, + .num_ext = ARRAY_SIZE(rz_mtu3_count_ext), + }, + { + .id = 2, + .name = "Channel3 Count(32-bit)", + .functions_list = rz_mtu3_count_functions, + .num_functions = ARRAY_SIZE(rz_mtu3_count_functions), + .synapses = rz_mtu3_count_synapses[0], + .num_synapses = 4, + .ext = rz_mtu3_count_ext, + .num_ext = ARRAY_SIZE(rz_mtu3_count_ext), + } +}; + +static int __maybe_unused rz_mtu3_cnt_pm_runtime_suspend(struct device *dev) +{ + struct rz_mtu3_cnt *const priv = dev_get_drvdata(dev); + + clk_disable_unprepare(priv->clk); + + return 0; +} + +static int __maybe_unused rz_mtu3_cnt_pm_runtime_resume(struct device *dev) +{ + struct rz_mtu3_cnt *const priv = dev_get_drvdata(dev); + + clk_prepare_enable(priv->clk); + + return 0; +} + +static const struct dev_pm_ops rz_mtu3_cnt_pm_ops = { + SET_RUNTIME_PM_OPS(rz_mtu3_cnt_pm_runtime_suspend, rz_mtu3_cnt_pm_runtime_resume, NULL) +}; + +static void rz_mtu3_cnt_pm_disable(void *data) +{ + struct device *dev = data; + + pm_runtime_disable(dev); + pm_runtime_set_suspended(dev); +} + +static int rz_mtu3_cnt_probe(struct platform_device *pdev) +{ + struct rz_mtu3 *ddata = dev_get_drvdata(pdev->dev.parent); + struct device *dev = &pdev->dev; + struct counter_device *counter; + struct rz_mtu3_cnt *priv; + unsigned int i; + int ret; + + counter = devm_counter_alloc(dev, sizeof(*priv)); + if (!counter) + return -ENOMEM; + + priv = counter_priv(counter); + priv->clk = ddata->clk; + + for (i = 0; i < RZ_MTU3_MAX_HW_CNTR_CHANNELS; i++) { + priv->ch[i] = &ddata->channels[RZ_MTU1 + i]; + priv->ch[i]->dev = dev; + if (priv->ch[i]->function != RZ_MTU3_NORMAL) + return dev_err_probe(dev, -EINVAL, + "channel '%u' is already claimed\n", i); + } + + mutex_init(&priv->lock); + clk_prepare_enable(priv->clk); + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + ret = devm_add_action_or_reset(&pdev->dev, + rz_mtu3_cnt_pm_disable, + dev); + if (ret < 0) + goto disable_clock; + + counter->name = dev_name(dev); + counter->parent = dev; + counter->ops = &rz_mtu3_cnt_ops; + counter->counts = rz_mtu3_counts; + counter->num_counts = ARRAY_SIZE(rz_mtu3_counts); + counter->signals = rz_mtu3_signals; + counter->num_signals = ARRAY_SIZE(rz_mtu3_signals); + platform_set_drvdata(pdev, priv); + + /* Register Counter device */ + ret = devm_counter_add(dev, counter); + if (ret < 0) { + dev_err_probe(dev, ret, "Failed to add counter\n"); + goto disable_clock; + } + + return 0; + +disable_clock: + clk_disable_unprepare(priv->clk); + + return ret; +} + +static const struct of_device_id rz_mtu3_cnt_of_match[] = { + { .compatible = "renesas,rz-mtu3-counter", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, rz_mtu3_cnt_of_match); + +static struct platform_driver rz_mtu3_cnt_driver = { + .probe = rz_mtu3_cnt_probe, + .driver = { + .name = "rz-mtu3-counter", + .pm = &rz_mtu3_cnt_pm_ops, + .of_match_table = rz_mtu3_cnt_of_match, + }, +}; +module_platform_driver(rz_mtu3_cnt_driver); + +MODULE_AUTHOR("Biju Das <biju.das.jz@xxxxxxxxxxxxxx>"); +MODULE_ALIAS("platform:rz-mtu3-counter"); +MODULE_DESCRIPTION("Renesas RZ/G2L MTU3a counter driver"); +MODULE_LICENSE("GPL"); +MODULE_IMPORT_NS(COUNTER); -- 2.25.1