* [PATCH v15 4/6] counter: Add Renesas RZ/G2L MTU3a counter driver
[not found] <20230330111632.169434-1-biju.das.jz@bp.renesas.com>
2023-03-30 11:16 ` [PATCH v15 3/6] Documentation: ABI: sysfs-bus-counter: add cascade_counts_enable and external_input_phase_clock_select Biju Das
@ 2023-03-30 11:16 ` Biju Das
2023-04-05 14:14 ` Lee Jones
2023-03-30 11:16 ` [PATCH v15 5/6] MAINTAINERS: Add entries for " Biju Das
2 siblings, 1 reply; 6+ messages in thread
From: Biju Das @ 2023-03-30 11:16 UTC (permalink / raw)
To: William Breathitt Gray
Cc: Biju Das, linux-iio, Lee Jones, Daniel Lezcano, Thierry Reding,
Uwe Kleine-König, Geert Uytterhoeven, Chris Paterson,
Prabhakar Mahadev Lad, linux-renesas-soc
Add RZ/G2L MTU3a counter driver. This IP supports the following
phase counting modes on MTU1 and MTU2 channels
1) 16-bit phase counting modes on MTU1 and MTU2 channels.
2) 32-bit phase counting mode by cascading MTU1 and MTU2 channels.
This patch adds 3 counter value channels.
count0: 16-bit phase counter value channel on MTU1
count1: 16-bit phase counter value channel on MTU2
count2: 32-bit phase counter value channel by cascading
MTU1 and MTU2 channels.
The external input phase clock pin for the counter value channels
are as follows:
count0: "MTCLKA-MTCLKB"
count1: "MTCLKA-MTCLKB" or "MTCLKC-MTCLKD"
count2: "MTCLKA-MTCLKB" or "MTCLKC-MTCLKD"
Use the sysfs variable "external_input_phase_clock_select" to select the
external input phase clock pin and "cascade_counts_enable" to enable/
disable cascading of channels.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: William Breathitt Gray <william.gray@linaro.org>
Acked-by: William Breathitt Gray <william.gray@linaro.org>
---
v14->v15:
* No change.
v13->v14:
* Added Acked-by tag from William Breathitt Gray
* Replaced RZ_MTU1->RZ_MTU3_CHAN_1 and retained the Rb/ack tag as
it is trivial change.
v12->v13:
* No change.
v11->v12:
* Updated header file to <linux/mfd/rz-mtu3.h> as core driver is moved to MFD.
v10->v11:
* Added Rb tag from William Breathitt Gray
* Replaced count2 channel name from "combined"->"cascaded", as channels
are cascaded
* Simplified the locking by adding the helper functions
rz_mtu3_lock_if_counter_is_valid, rz_mtu3_lock_if_count_is_enabled,
and rz_mtu3_lock_if_ch0_is_enabled.
v9->v10:
* Added helper function for rz_mtu3_count_{action,function}_read
* Added priv->lock in rz_mtu3_count_function_read and rz_mtu3_count_
direction_read.
* Added ch->is_busy check for rz_mtu3_action_read()
* Added rz_mtu3_is_ch0_enabled() for device specific sysfs variables.
* Added ch->is_busy check for device specific sysfs variables.
v8->v9:
* Added count_is_enabled variable to struct rz_mtu3_cnt
* Added check for ch->is_busy and count_is_enabled before every Counter
callback to ensure we do not try to access a busy channel used by other
subsystem(eg: pwm).
* Removed id parameter from rz_mtu3_32bit_cnt_setting()
* Made definition of rz_mtu3_get_ch() in single line.
* Replaced break->return in rz_mtu3_32bit_cnt_setting(),
rz_mtu3_count_function_read() and rz_mtu3_initialize_counter()
and removed redundant return 0.
* Simplified synapse signal check for rz_mtu3_action_read().
v7->v8:
* Simplified rz_mtu3_initialize_counter by calling rz_mtu3_request_
channel() and release the acquired sibling channel in case of error.
* Simplified rz_mtu3_terminate_counter by calling rz_mtu3_release_
channel().
* Removed unused ceiling and ch_id from rz_mtu3_count_write()
* Replaced the error -EINVAL->-EBUSY for rz_mtu3_is_counter_invalid()
* Avoided race between rz_mtu3_count_{read, write} with rz_mtu3_
cascade_counts_enable_set() by adding locks and moved the lock
before rz_mtu3_is_counter_invalid()
* Protected the rz_mtu3_count_ceiling_read() function with a lock
to make sure the cascade operation mode doesn't not change and
that the priv data structure accesses don't race when they are
changed in the ceiling_write() callback.
* Added lock in rz_mtu3_cascade_enable_set() to make sure the other
callbacks don't try to read the LWA state while updating LWA.
* Added lock in rz_mtu3_ext_input_phase_clock_select_set() to ensure
the other callbacks don't try to read the PHCKSEL state while updating
PHCKSEL.
* Added lock to avoid race between rz_mtu3_count_function_write() and
rz_mtu3_action_read()
* Updated rz_mtu3_action_read to return 0, if Synapse is in COUNTER_SYNAPSE
_ACTION_NONE state.
* Replaced sysfs variable cascade_enable->cascade_counts_enable
* Renamed rz_mtu3_cascade_enable_get->rz_mtu3_cascade_counts_enable_get
* Renamed rz_mtu3_cascade_enable_set->rz_mtu3_cascade_counts_enable_set
* Removed redundent ceiling assignment from rz_mtu3_count_ceiling_read()
* Removed unused ceiling and ch_id from rz_mtu3_count_write().
v6->v7:
* Updated commit description
* Added Register descriptions
* Opimized size of cache variable by using union
* Used test_bit() in rz_mtu3_is_counter_invalid()
* Replaced val->timer_mode in rz_mtu3_count_function_{read,write}
* Added TODO comment phase3 and phase5 modes.
* replaced if-else with ternary expression in rz_mtu3_count_direction_read()
* Used switch statement in rz_mtu3_count_ceiling_read to consistent with write
* Provided default case for all switch statement.
* Add mutex lock for avoiding races with other devices
* Updated comments in rz_mtu3_action_read
* Replaced COUNTER_COMP_DEVICE_BOOL->COUNTER_COMP_DEVICE_BOOL for
cascade_enable
* Replaced RZ_MTU3_GET_HW_CH->rz_mtu3_get_hw_ch
* Added rz_mtu3_get_ch() to get channels
* used rz_mtu3_shared_reg_update_bit for cascade_enable and
selecting phase input clock.
* Added rz_mtu3_is_counter_invalid() check in rz_mtu3_count_ceiling_read()
v5->v6:
* Updated KConfig and commit description
* Sorted header
* Fixed RZ_MTU3_GET_HW_CH Macro for argument reuse 'id' -
possible side-effects?
* Replaced SET_RUNTIME_PM_OPS->DEFINE_RUNTIME_DEV_PM_OPS and removed
__maybe_unused from suspend/resume()
v4->v5:
* Updated the Kconfig with SoC vendor name
* Introduced rz_mtu3_is_counter_invalid()
* replaced pointer to an array of struct rz_mtu3_channel with
a simple pointer to struct rz_mtu3_channel.
* Added long_word_access_ctrl_mode sysfs entry for 16-bit and
32-bit access
* Added external_input_phase_clock_select sysfs entry for
selecting input clocks.
* used preprocessor defines represent SIGNAL_{A,B,C,D}_ID instead of
signal ids.
v3->v4:
* There is no resource associated with "rz-mtu3-counter" compatible
and moved the code to mfd subsystem as it binds against "rz-mtu".
* Removed struct platform_driver rz_mtu3_cnt_driver.
* Updated commit description
* Updated Kconfig description
* Added macros RZ_MTU3_16_BIT_MTU{1,2}_CH for MTU1 and MTU2 channels
* Added RZ_MTU3_GET_HW_CH macro for getting channel ID.
* replaced priv->ch[id]->priv->ch[0] in rz_mtu3_count_read()
* Cached counter max values
* replaced cnt->tsr in rz_mtu3_count_direction_read()
* Added comments for RZ_MTU3_TCR_CCLR_NONE
* Replaced if with switch in rz_mtu3_initialize_counter() and
rz_mtu3_count_ceiling_write()
* Added locks in initialize, terminate and enable_read to prevent races.
* Updated rz_mtu3_action_read to take care of MTU2 signals.
* Added separate distinct array for each group of Synapse.
* Moved pm handling to parent.
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 | 11 +
drivers/counter/Makefile | 1 +
drivers/counter/rz-mtu3-cnt.c | 902 ++++++++++++++++++++++++++++++++++
3 files changed, 914 insertions(+)
create mode 100644 drivers/counter/rz-mtu3-cnt.c
diff --git a/drivers/counter/Kconfig b/drivers/counter/Kconfig
index b5ba8fb02cf7..4228be917038 100644
--- a/drivers/counter/Kconfig
+++ b/drivers/counter/Kconfig
@@ -73,6 +73,17 @@ config MICROCHIP_TCB_CAPTURE
To compile this driver as a module, choose M here: the
module will be called microchip-tcb-capture.
+config RZ_MTU3_CNT
+ tristate "Renesas RZ/G2L MTU3a counter driver"
+ depends on RZ_MTU3 || COMPILE_TEST
+ help
+ Enable support for MTU3a counter driver found on Renesas RZ/G2L alike
+ SoCs. This IP supports both 16-bit and 32-bit phase counting mode
+ support.
+
+ To compile this driver as a module, choose M here: the
+ module will be called rz-mtu3-cnt.
+
config STM32_LPTIMER_CNT
tristate "STM32 LP Timer encoder counter driver"
depends on MFD_STM32_LPTIMER || 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..a371bab68499
--- /dev/null
+++ b/drivers/counter/rz-mtu3-cnt.c
@@ -0,0 +1,902 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Renesas RZ/G2L MTU3a Counter driver
+ *
+ * Copyright (C) 2022 Renesas Electronics Corporation
+ */
+
+#include <linux/clk.h>
+#include <linux/counter.h>
+#include <linux/mfd/rz-mtu3.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/types.h>
+
+/*
+ * Register descriptions
+ * TSR: Timer Status Register
+ * TMDR1: Timer Mode Register 1
+ * TMDR3: Timer Mode Register 3
+ * TIOR: Timer I/O Control Register
+ * TCR: Timer Control Register
+ * TCNT: Timer Counter
+ * TGRA: Timer general register A
+ * TCNTLW: Timer Longword Counter
+ * TGRALW: Timer longword general register A
+ */
+
+#define RZ_MTU3_TSR_TCFD BIT(7) /* Count Direction Flag */
+
+#define RZ_MTU3_TMDR1_PH_CNT_MODE_1 (4) /* Phase counting mode 1 */
+#define RZ_MTU3_TMDR1_PH_CNT_MODE_2 (5) /* Phase counting mode 2 */
+#define RZ_MTU3_TMDR1_PH_CNT_MODE_3 (6) /* Phase counting mode 3 */
+#define RZ_MTU3_TMDR1_PH_CNT_MODE_4 (7) /* Phase counting mode 4 */
+#define RZ_MTU3_TMDR1_PH_CNT_MODE_5 (9) /* Phase counting mode 5 */
+#define RZ_MTU3_TMDR1_PH_CNT_MODE_MASK (0xf)
+
+/*
+ * LWA: MTU1/MTU2 Combination Longword Access Control
+ * 0: 16-bit, 1: 32-bit
+ */
+#define RZ_MTU3_TMDR3_LWA (0)
+
+/*
+ * PHCKSEL: External Input Phase Clock Select
+ * 0: MTCLKA and MTCLKB, 1: MTCLKC and MTCLKD
+ */
+#define RZ_MTU3_TMDR3_PHCKSEL (1)
+
+#define RZ_MTU3_16_BIT_MTU1_CH (0)
+#define RZ_MTU3_16_BIT_MTU2_CH (1)
+#define RZ_MTU3_32_BIT_CH (2)
+
+#define RZ_MTU3_TIOR_NO_OUTPUT (0) /* Output prohibited */
+#define RZ_MTU3_TIOR_IC_BOTH (10) /* Input capture at both edges */
+
+#define SIGNAL_A_ID (0)
+#define SIGNAL_B_ID (1)
+#define SIGNAL_C_ID (2)
+#define SIGNAL_D_ID (3)
+
+#define RZ_MTU3_MAX_HW_CNTR_CHANNELS (2)
+#define RZ_MTU3_MAX_LOGICAL_CNTR_CHANNELS (3)
+
+/**
+ * struct rz_mtu3_cnt - MTU3 counter private data
+ *
+ * @clk: MTU3 module clock
+ * @lock: Lock to prevent concurrent access for ceiling and count
+ * @ch: HW channels for the counters
+ * @count_is_enabled: Enabled state of Counter value channel
+ * @mtu_16bit_max: Cache for 16-bit counters
+ * @mtu_32bit_max: Cache for 32-bit counters
+ */
+struct rz_mtu3_cnt {
+ struct clk *clk;
+ struct mutex lock;
+ struct rz_mtu3_channel *ch;
+ bool count_is_enabled[RZ_MTU3_MAX_LOGICAL_CNTR_CHANNELS];
+ union {
+ u16 mtu_16bit_max[RZ_MTU3_MAX_HW_CNTR_CHANNELS];
+ u32 mtu_32bit_max;
+ };
+};
+
+static const enum counter_function rz_mtu3_count_functions[] = {
+ COUNTER_FUNCTION_QUADRATURE_X4,
+ COUNTER_FUNCTION_PULSE_DIRECTION,
+ COUNTER_FUNCTION_QUADRATURE_X2_B,
+};
+
+static inline size_t rz_mtu3_get_hw_ch(const size_t id)
+{
+ return (id == RZ_MTU3_32_BIT_CH) ? 0 : id;
+}
+
+static inline struct rz_mtu3_channel *rz_mtu3_get_ch(struct counter_device *counter, int id)
+{
+ struct rz_mtu3_cnt *const priv = counter_priv(counter);
+ const size_t ch_id = rz_mtu3_get_hw_ch(id);
+
+ return &priv->ch[ch_id];
+}
+
+static bool rz_mtu3_is_counter_invalid(struct counter_device *counter, int id)
+{
+ struct rz_mtu3_cnt *const priv = counter_priv(counter);
+ unsigned long tmdr;
+
+ pm_runtime_get_sync(priv->ch->dev);
+ tmdr = rz_mtu3_shared_reg_read(priv->ch, RZ_MTU3_TMDR3);
+ pm_runtime_put(priv->ch->dev);
+
+ if (id == RZ_MTU3_32_BIT_CH && test_bit(RZ_MTU3_TMDR3_LWA, &tmdr))
+ return false;
+
+ if (id != RZ_MTU3_32_BIT_CH && !test_bit(RZ_MTU3_TMDR3_LWA, &tmdr))
+ return false;
+
+ return true;
+}
+
+static int rz_mtu3_lock_if_counter_is_valid(struct counter_device *counter,
+ struct rz_mtu3_channel *const ch,
+ struct rz_mtu3_cnt *const priv,
+ int id)
+{
+ mutex_lock(&priv->lock);
+
+ if (ch->is_busy && !priv->count_is_enabled[id]) {
+ mutex_unlock(&priv->lock);
+ return -EINVAL;
+ }
+
+ if (rz_mtu3_is_counter_invalid(counter, id)) {
+ mutex_unlock(&priv->lock);
+ return -EBUSY;
+ }
+
+ return 0;
+}
+
+static int rz_mtu3_lock_if_count_is_enabled(struct rz_mtu3_channel *const ch,
+ struct rz_mtu3_cnt *const priv,
+ int id)
+{
+ mutex_lock(&priv->lock);
+
+ if (ch->is_busy && !priv->count_is_enabled[id]) {
+ mutex_unlock(&priv->lock);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int rz_mtu3_count_read(struct counter_device *counter,
+ struct counter_count *count, u64 *val)
+{
+ struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id);
+ struct rz_mtu3_cnt *const priv = counter_priv(counter);
+ int ret;
+
+ ret = rz_mtu3_lock_if_counter_is_valid(counter, ch, priv, count->id);
+ if (ret)
+ return ret;
+
+ pm_runtime_get_sync(ch->dev);
+ if (count->id == RZ_MTU3_32_BIT_CH)
+ *val = rz_mtu3_32bit_ch_read(ch, RZ_MTU3_TCNTLW);
+ else
+ *val = rz_mtu3_16bit_ch_read(ch, RZ_MTU3_TCNT);
+ pm_runtime_put(ch->dev);
+ mutex_unlock(&priv->lock);
+
+ return 0;
+}
+
+static int rz_mtu3_count_write(struct counter_device *counter,
+ struct counter_count *count, const u64 val)
+{
+ struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id);
+ struct rz_mtu3_cnt *const priv = counter_priv(counter);
+ int ret;
+
+ ret = rz_mtu3_lock_if_counter_is_valid(counter, ch, priv, count->id);
+ if (ret)
+ return ret;
+
+ pm_runtime_get_sync(ch->dev);
+ if (count->id == RZ_MTU3_32_BIT_CH)
+ rz_mtu3_32bit_ch_write(ch, RZ_MTU3_TCNTLW, val);
+ else
+ rz_mtu3_16bit_ch_write(ch, RZ_MTU3_TCNT, val);
+ pm_runtime_put(ch->dev);
+ mutex_unlock(&priv->lock);
+
+ return 0;
+}
+
+static int rz_mtu3_count_function_read_helper(struct rz_mtu3_channel *const ch,
+ struct rz_mtu3_cnt *const priv,
+ enum counter_function *function)
+{
+ u8 timer_mode;
+
+ pm_runtime_get_sync(ch->dev);
+ timer_mode = rz_mtu3_8bit_ch_read(ch, RZ_MTU3_TMDR1);
+ pm_runtime_put(ch->dev);
+
+ switch (timer_mode & RZ_MTU3_TMDR1_PH_CNT_MODE_MASK) {
+ case RZ_MTU3_TMDR1_PH_CNT_MODE_1:
+ *function = COUNTER_FUNCTION_QUADRATURE_X4;
+ return 0;
+ case RZ_MTU3_TMDR1_PH_CNT_MODE_2:
+ *function = COUNTER_FUNCTION_PULSE_DIRECTION;
+ return 0;
+ case RZ_MTU3_TMDR1_PH_CNT_MODE_4:
+ *function = COUNTER_FUNCTION_QUADRATURE_X2_B;
+ return 0;
+ default:
+ /*
+ * TODO:
+ * - need to add RZ_MTU3_TMDR1_PH_CNT_MODE_3
+ * - need to add RZ_MTU3_TMDR1_PH_CNT_MODE_5
+ */
+ return -EINVAL;
+ }
+}
+
+static int rz_mtu3_count_function_read(struct counter_device *counter,
+ struct counter_count *count,
+ enum counter_function *function)
+{
+ struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id);
+ struct rz_mtu3_cnt *const priv = counter_priv(counter);
+ int ret;
+
+ ret = rz_mtu3_lock_if_count_is_enabled(ch, priv, count->id);
+ if (ret)
+ return ret;
+
+ ret = rz_mtu3_count_function_read_helper(ch, priv, function);
+ mutex_unlock(&priv->lock);
+
+ return ret;
+}
+
+static int rz_mtu3_count_function_write(struct counter_device *counter,
+ struct counter_count *count,
+ enum counter_function function)
+{
+ struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id);
+ struct rz_mtu3_cnt *const priv = counter_priv(counter);
+ u8 timer_mode;
+ int ret;
+
+ ret = rz_mtu3_lock_if_count_is_enabled(ch, priv, count->id);
+ if (ret)
+ return ret;
+
+ switch (function) {
+ case COUNTER_FUNCTION_QUADRATURE_X4:
+ timer_mode = RZ_MTU3_TMDR1_PH_CNT_MODE_1;
+ break;
+ case COUNTER_FUNCTION_PULSE_DIRECTION:
+ timer_mode = RZ_MTU3_TMDR1_PH_CNT_MODE_2;
+ break;
+ case COUNTER_FUNCTION_QUADRATURE_X2_B:
+ timer_mode = RZ_MTU3_TMDR1_PH_CNT_MODE_4;
+ break;
+ default:
+ /*
+ * TODO:
+ * - need to add RZ_MTU3_TMDR1_PH_CNT_MODE_3
+ * - need to add RZ_MTU3_TMDR1_PH_CNT_MODE_5
+ */
+ mutex_unlock(&priv->lock);
+ return -EINVAL;
+ }
+
+ pm_runtime_get_sync(ch->dev);
+ rz_mtu3_8bit_ch_write(ch, RZ_MTU3_TMDR1, timer_mode);
+ pm_runtime_put(ch->dev);
+ mutex_unlock(&priv->lock);
+
+ 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_channel *const ch = rz_mtu3_get_ch(counter, count->id);
+ struct rz_mtu3_cnt *const priv = counter_priv(counter);
+ int ret;
+ u8 tsr;
+
+ ret = rz_mtu3_lock_if_count_is_enabled(ch, priv, count->id);
+ if (ret)
+ return ret;
+
+ pm_runtime_get_sync(ch->dev);
+ tsr = rz_mtu3_8bit_ch_read(ch, RZ_MTU3_TSR);
+ pm_runtime_put(ch->dev);
+
+ *direction = (tsr & RZ_MTU3_TSR_TCFD) ?
+ COUNTER_COUNT_DIRECTION_FORWARD : COUNTER_COUNT_DIRECTION_BACKWARD;
+ mutex_unlock(&priv->lock);
+
+ return 0;
+}
+
+static int rz_mtu3_count_ceiling_read(struct counter_device *counter,
+ struct counter_count *count,
+ u64 *ceiling)
+{
+ struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id);
+ struct rz_mtu3_cnt *const priv = counter_priv(counter);
+ const size_t ch_id = rz_mtu3_get_hw_ch(count->id);
+ int ret;
+
+ ret = rz_mtu3_lock_if_counter_is_valid(counter, ch, priv, count->id);
+ if (ret)
+ return ret;
+
+ switch (count->id) {
+ case RZ_MTU3_16_BIT_MTU1_CH:
+ case RZ_MTU3_16_BIT_MTU2_CH:
+ *ceiling = priv->mtu_16bit_max[ch_id];
+ break;
+ case RZ_MTU3_32_BIT_CH:
+ *ceiling = priv->mtu_32bit_max;
+ break;
+ default:
+ /* should never reach this path */
+ mutex_unlock(&priv->lock);
+ return -EINVAL;
+ }
+
+ mutex_unlock(&priv->lock);
+ return 0;
+}
+
+static int rz_mtu3_count_ceiling_write(struct counter_device *counter,
+ struct counter_count *count,
+ u64 ceiling)
+{
+ struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id);
+ struct rz_mtu3_cnt *const priv = counter_priv(counter);
+ const size_t ch_id = rz_mtu3_get_hw_ch(count->id);
+ int ret;
+
+ ret = rz_mtu3_lock_if_counter_is_valid(counter, ch, priv, count->id);
+ if (ret)
+ return ret;
+
+ switch (count->id) {
+ case RZ_MTU3_16_BIT_MTU1_CH:
+ case RZ_MTU3_16_BIT_MTU2_CH:
+ if (ceiling > U16_MAX)
+ return -ERANGE;
+ priv->mtu_16bit_max[ch_id] = ceiling;
+ break;
+ case RZ_MTU3_32_BIT_CH:
+ if (ceiling > U32_MAX)
+ return -ERANGE;
+ priv->mtu_32bit_max = ceiling;
+ break;
+ default:
+ /* should never reach this path */
+ mutex_unlock(&priv->lock);
+ return -EINVAL;
+ }
+
+ pm_runtime_get_sync(ch->dev);
+ if (count->id == RZ_MTU3_32_BIT_CH)
+ rz_mtu3_32bit_ch_write(ch, RZ_MTU3_TGRALW, ceiling);
+ else
+ rz_mtu3_16bit_ch_write(ch, RZ_MTU3_TGRA, ceiling);
+
+ rz_mtu3_8bit_ch_write(ch, RZ_MTU3_TCR, RZ_MTU3_TCR_CCLR_TGRA);
+ pm_runtime_put(ch->dev);
+ mutex_unlock(&priv->lock);
+
+ return 0;
+}
+
+static void rz_mtu3_32bit_cnt_setting(struct counter_device *counter)
+{
+ struct rz_mtu3_channel *const ch1 = rz_mtu3_get_ch(counter, 0);
+ struct rz_mtu3_channel *const ch2 = rz_mtu3_get_ch(counter, 1);
+
+ /* Phase counting mode 1 is used as default in initialization. */
+ rz_mtu3_8bit_ch_write(ch1, RZ_MTU3_TMDR1, RZ_MTU3_TMDR1_PH_CNT_MODE_1);
+
+ rz_mtu3_8bit_ch_write(ch1, RZ_MTU3_TCR, RZ_MTU3_TCR_CCLR_TGRA);
+ rz_mtu3_8bit_ch_write(ch1, RZ_MTU3_TIOR, RZ_MTU3_TIOR_IC_BOTH);
+
+ rz_mtu3_enable(ch1);
+ rz_mtu3_enable(ch2);
+}
+
+static void rz_mtu3_16bit_cnt_setting(struct counter_device *counter, int id)
+{
+ struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, id);
+
+ /* Phase counting mode 1 is used as default in initialization. */
+ rz_mtu3_8bit_ch_write(ch, RZ_MTU3_TMDR1, RZ_MTU3_TMDR1_PH_CNT_MODE_1);
+
+ rz_mtu3_8bit_ch_write(ch, RZ_MTU3_TCR, RZ_MTU3_TCR_CCLR_TGRA);
+ rz_mtu3_8bit_ch_write(ch, RZ_MTU3_TIOR, RZ_MTU3_TIOR_NO_OUTPUT);
+ rz_mtu3_enable(ch);
+}
+
+static int rz_mtu3_initialize_counter(struct counter_device *counter, int id)
+{
+ struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, id);
+ struct rz_mtu3_channel *const ch1 = rz_mtu3_get_ch(counter, 0);
+ struct rz_mtu3_channel *const ch2 = rz_mtu3_get_ch(counter, 1);
+
+ switch (id) {
+ case RZ_MTU3_16_BIT_MTU1_CH:
+ case RZ_MTU3_16_BIT_MTU2_CH:
+ if (!rz_mtu3_request_channel(ch))
+ return -EBUSY;
+
+ rz_mtu3_16bit_cnt_setting(counter, id);
+ return 0;
+ case RZ_MTU3_32_BIT_CH:
+ /*
+ * 32-bit phase counting need MTU1 and MTU2 to create 32-bit
+ * cascade counter.
+ */
+ if (!rz_mtu3_request_channel(ch1))
+ return -EBUSY;
+
+ if (!rz_mtu3_request_channel(ch2)) {
+ rz_mtu3_release_channel(ch1);
+ return -EBUSY;
+ }
+
+ rz_mtu3_32bit_cnt_setting(counter);
+ return 0;
+ default:
+ /* should never reach this path */
+ return -EINVAL;
+ }
+}
+
+static void rz_mtu3_terminate_counter(struct counter_device *counter, int id)
+{
+ struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, id);
+ struct rz_mtu3_channel *const ch1 = rz_mtu3_get_ch(counter, 0);
+ struct rz_mtu3_channel *const ch2 = rz_mtu3_get_ch(counter, 1);
+
+ if (id == RZ_MTU3_32_BIT_CH) {
+ rz_mtu3_release_channel(ch2);
+ rz_mtu3_release_channel(ch1);
+ rz_mtu3_disable(ch2);
+ rz_mtu3_disable(ch1);
+ } else {
+ rz_mtu3_release_channel(ch);
+ rz_mtu3_disable(ch);
+ }
+}
+
+static int rz_mtu3_count_enable_read(struct counter_device *counter,
+ struct counter_count *count, u8 *enable)
+{
+ struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id);
+ struct rz_mtu3_channel *const ch1 = rz_mtu3_get_ch(counter, 0);
+ struct rz_mtu3_channel *const ch2 = rz_mtu3_get_ch(counter, 1);
+ struct rz_mtu3_cnt *const priv = counter_priv(counter);
+ int ret;
+
+ ret = rz_mtu3_lock_if_count_is_enabled(ch, priv, count->id);
+ if (ret)
+ return ret;
+
+ if (count->id == RZ_MTU3_32_BIT_CH)
+ *enable = rz_mtu3_is_enabled(ch1) && rz_mtu3_is_enabled(ch2);
+ else
+ *enable = rz_mtu3_is_enabled(ch);
+
+ mutex_unlock(&priv->lock);
+
+ return 0;
+}
+
+static int rz_mtu3_count_enable_write(struct counter_device *counter,
+ struct counter_count *count, u8 enable)
+{
+ struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id);
+ struct rz_mtu3_cnt *const priv = counter_priv(counter);
+ int ret = 0;
+
+ if (enable) {
+ pm_runtime_get_sync(ch->dev);
+ mutex_lock(&priv->lock);
+ ret = rz_mtu3_initialize_counter(counter, count->id);
+ if (ret == 0)
+ priv->count_is_enabled[count->id] = true;
+ mutex_unlock(&priv->lock);
+ } else {
+ mutex_lock(&priv->lock);
+ rz_mtu3_terminate_counter(counter, count->id);
+ priv->count_is_enabled[count->id] = false;
+ mutex_unlock(&priv->lock);
+ pm_runtime_put(ch->dev);
+ }
+
+ return ret;
+}
+
+static int rz_mtu3_lock_if_ch0_is_enabled(struct rz_mtu3_cnt *const priv)
+{
+ mutex_lock(&priv->lock);
+ if (priv->ch->is_busy && !(priv->count_is_enabled[RZ_MTU3_16_BIT_MTU1_CH] ||
+ priv->count_is_enabled[RZ_MTU3_32_BIT_CH])) {
+ mutex_unlock(&priv->lock);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int rz_mtu3_cascade_counts_enable_get(struct counter_device *counter,
+ u8 *cascade_enable)
+{
+ struct rz_mtu3_cnt *const priv = counter_priv(counter);
+ unsigned long tmdr;
+ int ret;
+
+ ret = rz_mtu3_lock_if_ch0_is_enabled(priv);
+ if (ret)
+ return ret;
+
+ pm_runtime_get_sync(priv->ch->dev);
+ tmdr = rz_mtu3_shared_reg_read(priv->ch, RZ_MTU3_TMDR3);
+ pm_runtime_put(priv->ch->dev);
+ *cascade_enable = test_bit(RZ_MTU3_TMDR3_LWA, &tmdr);
+ mutex_unlock(&priv->lock);
+
+ return 0;
+}
+
+static int rz_mtu3_cascade_counts_enable_set(struct counter_device *counter,
+ u8 cascade_enable)
+{
+ struct rz_mtu3_cnt *const priv = counter_priv(counter);
+ int ret;
+
+ ret = rz_mtu3_lock_if_ch0_is_enabled(priv);
+ if (ret)
+ return ret;
+
+ pm_runtime_get_sync(priv->ch->dev);
+ rz_mtu3_shared_reg_update_bit(priv->ch, RZ_MTU3_TMDR3,
+ RZ_MTU3_TMDR3_LWA, cascade_enable);
+ pm_runtime_put(priv->ch->dev);
+ mutex_unlock(&priv->lock);
+
+ return 0;
+}
+
+static int rz_mtu3_ext_input_phase_clock_select_get(struct counter_device *counter,
+ u32 *ext_input_phase_clock_select)
+{
+ struct rz_mtu3_cnt *const priv = counter_priv(counter);
+ unsigned long tmdr;
+ int ret;
+
+ ret = rz_mtu3_lock_if_ch0_is_enabled(priv);
+ if (ret)
+ return ret;
+
+ pm_runtime_get_sync(priv->ch->dev);
+ tmdr = rz_mtu3_shared_reg_read(priv->ch, RZ_MTU3_TMDR3);
+ pm_runtime_put(priv->ch->dev);
+ *ext_input_phase_clock_select = test_bit(RZ_MTU3_TMDR3_PHCKSEL, &tmdr);
+ mutex_unlock(&priv->lock);
+
+ return 0;
+}
+
+static int rz_mtu3_ext_input_phase_clock_select_set(struct counter_device *counter,
+ u32 ext_input_phase_clock_select)
+{
+ struct rz_mtu3_cnt *const priv = counter_priv(counter);
+ int ret;
+
+ ret = rz_mtu3_lock_if_ch0_is_enabled(priv);
+ if (ret)
+ return ret;
+
+ pm_runtime_get_sync(priv->ch->dev);
+ rz_mtu3_shared_reg_update_bit(priv->ch, RZ_MTU3_TMDR3,
+ RZ_MTU3_TMDR3_PHCKSEL,
+ ext_input_phase_clock_select);
+ pm_runtime_put(priv->ch->dev);
+ mutex_unlock(&priv->lock);
+
+ return 0;
+}
+
+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 bool is_signal_ab = (synapse->signal->id == SIGNAL_A_ID) ||
+ (synapse->signal->id == SIGNAL_B_ID);
+ struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id);
+ struct rz_mtu3_cnt *const priv = counter_priv(counter);
+ enum counter_function function;
+ bool mtclkc_mtclkd;
+ unsigned long tmdr;
+ int ret;
+
+ ret = rz_mtu3_lock_if_count_is_enabled(ch, priv, count->id);
+ if (ret)
+ return ret;
+
+ ret = rz_mtu3_count_function_read_helper(ch, priv, &function);
+ if (ret) {
+ mutex_unlock(&priv->lock);
+ return ret;
+ }
+
+ /* Default action mode */
+ *action = COUNTER_SYNAPSE_ACTION_NONE;
+
+ if (count->id != RZ_MTU3_16_BIT_MTU1_CH) {
+ tmdr = rz_mtu3_shared_reg_read(priv->ch, RZ_MTU3_TMDR3);
+ mtclkc_mtclkd = test_bit(RZ_MTU3_TMDR3_PHCKSEL, &tmdr);
+ if ((mtclkc_mtclkd && is_signal_ab) ||
+ (!mtclkc_mtclkd && !is_signal_ab)) {
+ mutex_unlock(&priv->lock);
+ return 0;
+ }
+ }
+
+ switch (function) {
+ case COUNTER_FUNCTION_PULSE_DIRECTION:
+ /*
+ * Rising edges on signal A (signal C) updates the respective
+ * count. The input level of signal B (signal D) determines
+ * direction.
+ */
+ if (synapse->signal->id == SIGNAL_A_ID ||
+ synapse->signal->id == SIGNAL_C_ID)
+ *action = COUNTER_SYNAPSE_ACTION_RISING_EDGE;
+ break;
+ case COUNTER_FUNCTION_QUADRATURE_X2_B:
+ /*
+ * Any state transition on quadrature pair signal B (signal D)
+ * updates the respective count.
+ */
+ if (synapse->signal->id == SIGNAL_B_ID ||
+ synapse->signal->id == SIGNAL_D_ID)
+ *action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
+ break;
+ case COUNTER_FUNCTION_QUADRATURE_X4:
+ /* counts up/down on both edges of A (C) and B (D) signal */
+ *action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
+ break;
+ default:
+ /* should never reach this path */
+ mutex_unlock(&priv->lock);
+ return -EINVAL;
+ }
+
+ mutex_unlock(&priv->lock);
+
+ 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(SIGNAL_A_ID, "MTU1 MTCLKA"),
+ RZ_MTU3_PHASE_SIGNAL(SIGNAL_B_ID, "MTU1 MTCLKB"),
+ RZ_MTU3_PHASE_SIGNAL(SIGNAL_C_ID, "MTU2 MTCLKC"),
+ RZ_MTU3_PHASE_SIGNAL(SIGNAL_D_ID, "MTU2 MTCLKD"),
+};
+
+static struct counter_synapse rz_mtu3_mtu1_count_synapses[] = {
+ {
+ .actions_list = rz_mtu3_synapse_actions,
+ .num_actions = ARRAY_SIZE(rz_mtu3_synapse_actions),
+ .signal = rz_mtu3_signals,
+ },
+ {
+ .actions_list = rz_mtu3_synapse_actions,
+ .num_actions = ARRAY_SIZE(rz_mtu3_synapse_actions),
+ .signal = rz_mtu3_signals + 1,
+ }
+};
+
+static struct counter_synapse rz_mtu3_mtu2_count_synapses[] = {
+ {
+ .actions_list = rz_mtu3_synapse_actions,
+ .num_actions = ARRAY_SIZE(rz_mtu3_synapse_actions),
+ .signal = rz_mtu3_signals,
+ },
+ {
+ .actions_list = rz_mtu3_synapse_actions,
+ .num_actions = ARRAY_SIZE(rz_mtu3_synapse_actions),
+ .signal = rz_mtu3_signals + 1,
+ },
+ {
+ .actions_list = rz_mtu3_synapse_actions,
+ .num_actions = ARRAY_SIZE(rz_mtu3_synapse_actions),
+ .signal = rz_mtu3_signals + 2,
+ },
+ {
+ .actions_list = rz_mtu3_synapse_actions,
+ .num_actions = ARRAY_SIZE(rz_mtu3_synapse_actions),
+ .signal = rz_mtu3_signals + 3,
+ }
+};
+
+static struct counter_count rz_mtu3_counts[] = {
+ {
+ .id = RZ_MTU3_16_BIT_MTU1_CH,
+ .name = "Channel 1 Count",
+ .functions_list = rz_mtu3_count_functions,
+ .num_functions = ARRAY_SIZE(rz_mtu3_count_functions),
+ .synapses = rz_mtu3_mtu1_count_synapses,
+ .num_synapses = ARRAY_SIZE(rz_mtu3_mtu1_count_synapses),
+ .ext = rz_mtu3_count_ext,
+ .num_ext = ARRAY_SIZE(rz_mtu3_count_ext),
+ },
+ {
+ .id = RZ_MTU3_16_BIT_MTU2_CH,
+ .name = "Channel 2 Count",
+ .functions_list = rz_mtu3_count_functions,
+ .num_functions = ARRAY_SIZE(rz_mtu3_count_functions),
+ .synapses = rz_mtu3_mtu2_count_synapses,
+ .num_synapses = ARRAY_SIZE(rz_mtu3_mtu2_count_synapses),
+ .ext = rz_mtu3_count_ext,
+ .num_ext = ARRAY_SIZE(rz_mtu3_count_ext),
+ },
+ {
+ .id = RZ_MTU3_32_BIT_CH,
+ .name = "Channel 1 and 2 (cascaded) Count",
+ .functions_list = rz_mtu3_count_functions,
+ .num_functions = ARRAY_SIZE(rz_mtu3_count_functions),
+ .synapses = rz_mtu3_mtu2_count_synapses,
+ .num_synapses = ARRAY_SIZE(rz_mtu3_mtu2_count_synapses),
+ .ext = rz_mtu3_count_ext,
+ .num_ext = ARRAY_SIZE(rz_mtu3_count_ext),
+ }
+};
+
+static const char *const rz_mtu3_ext_input_phase_clock_select[] = {
+ "MTCLKA-MTCLKB",
+ "MTCLKC-MTCLKD",
+};
+
+static DEFINE_COUNTER_ENUM(rz_mtu3_ext_input_phase_clock_select_enum,
+ rz_mtu3_ext_input_phase_clock_select);
+
+static struct counter_comp rz_mtu3_device_ext[] = {
+ COUNTER_COMP_DEVICE_BOOL("cascade_counts_enable",
+ rz_mtu3_cascade_counts_enable_get,
+ rz_mtu3_cascade_counts_enable_set),
+ COUNTER_COMP_DEVICE_ENUM("external_input_phase_clock_select",
+ rz_mtu3_ext_input_phase_clock_select_get,
+ rz_mtu3_ext_input_phase_clock_select_set,
+ rz_mtu3_ext_input_phase_clock_select_enum),
+};
+
+static int rz_mtu3_cnt_pm_runtime_suspend(struct device *dev)
+{
+ struct clk *const clk = dev_get_drvdata(dev);
+
+ clk_disable_unprepare(clk);
+
+ return 0;
+}
+
+static int rz_mtu3_cnt_pm_runtime_resume(struct device *dev)
+{
+ struct clk *const clk = dev_get_drvdata(dev);
+
+ clk_prepare_enable(clk);
+
+ return 0;
+}
+
+static DEFINE_RUNTIME_DEV_PM_OPS(rz_mtu3_cnt_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_channel *ch;
+ 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;
+ priv->mtu_32bit_max = U32_MAX;
+ priv->ch = &ddata->channels[RZ_MTU3_CHAN_1];
+ ch = &priv->ch[0];
+ for (i = 0; i < RZ_MTU3_MAX_HW_CNTR_CHANNELS; i++) {
+ ch->dev = dev;
+ priv->mtu_16bit_max[i] = U16_MAX;
+ ch++;
+ }
+
+ mutex_init(&priv->lock);
+ platform_set_drvdata(pdev, priv->clk);
+ 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);
+ counter->ext = rz_mtu3_device_ext;
+ counter->num_ext = ARRAY_SIZE(rz_mtu3_device_ext);
+
+ /* 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 struct platform_driver rz_mtu3_cnt_driver = {
+ .probe = rz_mtu3_cnt_probe,
+ .driver = {
+ .name = "rz-mtu3-counter",
+ .pm = pm_ptr(&rz_mtu3_cnt_pm_ops),
+ },
+};
+module_platform_driver(rz_mtu3_cnt_driver);
+
+MODULE_AUTHOR("Biju Das <biju.das.jz@bp.renesas.com>");
+MODULE_ALIAS("platform:rz-mtu3-counter");
+MODULE_DESCRIPTION("Renesas RZ/G2L MTU3a counter driver");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(COUNTER);
--
2.25.1
^ permalink raw reply related [flat|nested] 6+ messages in thread