2023-08-14 11:30:10

by MD Danish Anwar

[permalink] [raw]
Subject: [PATCH v4 3/5] net: ti: icss-iep: Add IEP driver

From: Roger Quadros <[email protected]>

Add a driver for Industrial Ethernet Peripheral (IEP) block of PRUSS to
support timestamping of ethernet packets and thus support PTP and PPS
for PRU ethernet ports.

Signed-off-by: Roger Quadros <[email protected]>
Signed-off-by: Lokesh Vutla <[email protected]>
Signed-off-by: Murali Karicheri <[email protected]>
Signed-off-by: Vignesh Raghavendra <[email protected]>
Signed-off-by: MD Danish Anwar <[email protected]>
---
drivers/net/ethernet/ti/Kconfig | 11 +
drivers/net/ethernet/ti/Makefile | 1 +
drivers/net/ethernet/ti/icssg/icss_iep.c | 921 +++++++++++++++++++++++
drivers/net/ethernet/ti/icssg/icss_iep.h | 38 +
4 files changed, 971 insertions(+)
create mode 100644 drivers/net/ethernet/ti/icssg/icss_iep.c
create mode 100644 drivers/net/ethernet/ti/icssg/icss_iep.h

diff --git a/drivers/net/ethernet/ti/Kconfig b/drivers/net/ethernet/ti/Kconfig
index 63e510b6860f..1af5a90720ec 100644
--- a/drivers/net/ethernet/ti/Kconfig
+++ b/drivers/net/ethernet/ti/Kconfig
@@ -196,4 +196,15 @@ config TI_ICSSG_PRUETH
to support the Ethernet operation. Currently, it supports Ethernet
with 1G and 100M link speed.

+config TI_ICSS_IEP
+ tristate "TI PRU ICSS IEP driver"
+ depends on TI_PRUSS
+ default TI_PRUSS
+ help
+ This driver enables support for the PRU-ICSS Industrial Ethernet
+ Peripheral within a PRU-ICSS subsystem present on various TI SoCs.
+
+ To compile this driver as a module, choose M here. The module
+ will be called icss_iep.
+
endif # NET_VENDOR_TI
diff --git a/drivers/net/ethernet/ti/Makefile b/drivers/net/ethernet/ti/Makefile
index 9176d79c36e1..34fd7a716ba6 100644
--- a/drivers/net/ethernet/ti/Makefile
+++ b/drivers/net/ethernet/ti/Makefile
@@ -38,3 +38,4 @@ icssg-prueth-y := k3-cppi-desc-pool.o \
icssg/icssg_mii_cfg.o \
icssg/icssg_stats.o \
icssg/icssg_ethtool.o
+obj-$(CONFIG_TI_ICSS_IEP) += icssg/icss_iep.o
diff --git a/drivers/net/ethernet/ti/icssg/icss_iep.c b/drivers/net/ethernet/ti/icssg/icss_iep.c
new file mode 100644
index 000000000000..d123b8ba3f31
--- /dev/null
+++ b/drivers/net/ethernet/ti/icssg/icss_iep.c
@@ -0,0 +1,921 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/* Texas Instruments ICSSG Industrial Ethernet Peripheral (IEP) Driver
+ *
+ * Copyright (C) 2023 Texas Instruments Incorporated - https://www.ti.com
+ *
+ */
+
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/timekeeping.h>
+#include <linux/interrupt.h>
+#include <linux/of_irq.h>
+
+#include "icss_iep.h"
+
+#define IEP_MAX_DEF_INC 0xf
+#define IEP_MAX_COMPEN_INC 0xfff
+#define IEP_MAX_COMPEN_COUNT 0xffffff
+
+#define IEP_GLOBAL_CFG_CNT_ENABLE BIT(0)
+#define IEP_GLOBAL_CFG_DEFAULT_INC_MASK GENMASK(7, 4)
+#define IEP_GLOBAL_CFG_DEFAULT_INC_SHIFT 4
+#define IEP_GLOBAL_CFG_COMPEN_INC_MASK GENMASK(19, 8)
+#define IEP_GLOBAL_CFG_COMPEN_INC_SHIFT 8
+
+#define IEP_GLOBAL_STATUS_CNT_OVF BIT(0)
+
+#define IEP_CMP_CFG_SHADOW_EN BIT(17)
+#define IEP_CMP_CFG_CMP0_RST_CNT_EN BIT(0)
+#define IEP_CMP_CFG_CMP_EN(cmp) (GENMASK(16, 1) & (1 << ((cmp) + 1)))
+
+#define IEP_CMP_STATUS(cmp) (1 << (cmp))
+
+#define IEP_SYNC_CTRL_SYNC_EN BIT(0)
+#define IEP_SYNC_CTRL_SYNC_N_EN(n) (GENMASK(2, 1) & (BIT(1) << (n)))
+
+#define IEP_MIN_CMP 0
+#define IEP_MAX_CMP 15
+
+#define ICSS_IEP_64BIT_COUNTER_SUPPORT BIT(0)
+#define ICSS_IEP_SLOW_COMPEN_REG_SUPPORT BIT(1)
+#define ICSS_IEP_SHADOW_MODE_SUPPORT BIT(2)
+
+#define LATCH_INDEX(ts_index) ((ts_index) + 6)
+#define IEP_CAP_CFG_CAPNR_1ST_EVENT_EN(n) BIT(LATCH_INDEX(n))
+#define IEP_CAP_CFG_CAP_ASYNC_EN(n) BIT(LATCH_INDEX(n) + 10)
+
+enum {
+ ICSS_IEP_GLOBAL_CFG_REG,
+ ICSS_IEP_GLOBAL_STATUS_REG,
+ ICSS_IEP_COMPEN_REG,
+ ICSS_IEP_SLOW_COMPEN_REG,
+ ICSS_IEP_COUNT_REG0,
+ ICSS_IEP_COUNT_REG1,
+ ICSS_IEP_CAPTURE_CFG_REG,
+ ICSS_IEP_CAPTURE_STAT_REG,
+
+ ICSS_IEP_CAP6_RISE_REG0,
+ ICSS_IEP_CAP6_RISE_REG1,
+
+ ICSS_IEP_CAP7_RISE_REG0,
+ ICSS_IEP_CAP7_RISE_REG1,
+
+ ICSS_IEP_CMP_CFG_REG,
+ ICSS_IEP_CMP_STAT_REG,
+ ICSS_IEP_CMP0_REG0,
+ ICSS_IEP_CMP0_REG1,
+ ICSS_IEP_CMP1_REG0,
+ ICSS_IEP_CMP1_REG1,
+
+ ICSS_IEP_CMP8_REG0,
+ ICSS_IEP_CMP8_REG1,
+ ICSS_IEP_SYNC_CTRL_REG,
+ ICSS_IEP_SYNC0_STAT_REG,
+ ICSS_IEP_SYNC1_STAT_REG,
+ ICSS_IEP_SYNC_PWIDTH_REG,
+ ICSS_IEP_SYNC0_PERIOD_REG,
+ ICSS_IEP_SYNC1_DELAY_REG,
+ ICSS_IEP_SYNC_START_REG,
+ ICSS_IEP_MAX_REGS,
+};
+
+/**
+ * struct icss_iep_plat_data - Plat data to handle SoC variants
+ * @config: Regmap configuration data
+ * @reg_offs: register offsets to capture offset differences across SoCs
+ * @flags: Flags to represent IEP properties
+ */
+struct icss_iep_plat_data {
+ struct regmap_config *config;
+ u32 reg_offs[ICSS_IEP_MAX_REGS];
+ u32 flags;
+};
+
+struct icss_iep {
+ struct device *dev;
+ void __iomem *base;
+ const struct icss_iep_plat_data *plat_data;
+ struct regmap *map;
+ struct device_node *client_np;
+ unsigned long refclk_freq;
+ int clk_tick_time; /* one refclk tick time in ns */
+ struct ptp_clock_info ptp_info;
+ struct ptp_clock *ptp_clock;
+ struct mutex ptp_clk_mutex; /* PHC access serializer */
+ spinlock_t irq_lock; /* CMP IRQ vs icss_iep_ptp_enable access */
+ u32 def_inc;
+ s16 slow_cmp_inc;
+ u32 slow_cmp_count;
+ const struct icss_iep_clockops *ops;
+ void *clockops_data;
+ u32 cycle_time_ns;
+ u32 perout_enabled;
+ bool pps_enabled;
+ int cap_cmp_irq;
+ u64 period;
+ u32 latch_enable;
+};
+
+/**
+ * icss_iep_get_count_hi() - Get the upper 32 bit IEP counter
+ * @iep: Pointer to structure representing IEP.
+ *
+ * Return: upper 32 bit IEP counter
+ */
+int icss_iep_get_count_hi(struct icss_iep *iep)
+{
+ u32 val = 0;
+
+ if (iep && (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT))
+ val = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG1]);
+
+ return val;
+}
+EXPORT_SYMBOL_GPL(icss_iep_get_count_hi);
+
+/**
+ * icss_iep_get_count_low() - Get the lower 32 bit IEP counter
+ * @iep: Pointer to structure representing IEP.
+ *
+ * Return: lower 32 bit IEP counter
+ */
+int icss_iep_get_count_low(struct icss_iep *iep)
+{
+ u32 val = 0;
+
+ if (iep)
+ val = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG0]);
+
+ return val;
+}
+EXPORT_SYMBOL_GPL(icss_iep_get_count_low);
+
+/**
+ * icss_iep_get_ptp_clock_idx() - Get PTP clock index using IEP driver
+ * @iep: Pointer to structure representing IEP.
+ *
+ * Return: PTP clock index, -1 if not registered
+ */
+int icss_iep_get_ptp_clock_idx(struct icss_iep *iep)
+{
+ if (!iep || !iep->ptp_clock)
+ return -1;
+ return ptp_clock_index(iep->ptp_clock);
+}
+EXPORT_SYMBOL_GPL(icss_iep_get_ptp_clock_idx);
+
+static void icss_iep_set_counter(struct icss_iep *iep, u64 ns)
+{
+ if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
+ writel(upper_32_bits(ns), iep->base +
+ iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG1]);
+ writel(upper_32_bits(ns), iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG0]);
+}
+
+static void icss_iep_update_to_next_boundary(struct icss_iep *iep, u64 start_ns);
+
+static void icss_iep_settime(struct icss_iep *iep, u64 ns)
+{
+ unsigned long flags;
+
+ if (iep->ops && iep->ops->settime) {
+ iep->ops->settime(iep->clockops_data, ns);
+ return;
+ }
+
+ spin_lock_irqsave(&iep->irq_lock, flags);
+ if (iep->pps_enabled || iep->perout_enabled)
+ writel(0, iep->base + iep->plat_data->reg_offs[ICSS_IEP_SYNC_CTRL_REG]);
+
+ icss_iep_set_counter(iep, ns);
+
+ if (iep->pps_enabled || iep->perout_enabled) {
+ icss_iep_update_to_next_boundary(iep, ns);
+ writel(IEP_SYNC_CTRL_SYNC_N_EN(0) | IEP_SYNC_CTRL_SYNC_EN,
+ iep->base + iep->plat_data->reg_offs[ICSS_IEP_SYNC_CTRL_REG]);
+ }
+ spin_unlock_irqrestore(&iep->irq_lock, flags);
+}
+
+static u64 icss_iep_gettime(struct icss_iep *iep,
+ struct ptp_system_timestamp *sts)
+{
+ u32 ts_hi = 0, ts_lo;
+ unsigned long flags;
+
+ if (iep->ops && iep->ops->gettime)
+ return iep->ops->gettime(iep->clockops_data, sts);
+
+ /* use local_irq_x() to make it work for both RT/non-RT */
+ local_irq_save(flags);
+
+ /* no need to play with hi-lo, hi is latched when lo is read */
+ ptp_read_system_prets(sts);
+ ts_lo = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG0]);
+ ptp_read_system_postts(sts);
+ if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
+ ts_hi = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG1]);
+
+ local_irq_restore(flags);
+
+ return (u64)ts_lo | (u64)ts_hi << 32;
+}
+
+static void icss_iep_enable(struct icss_iep *iep)
+{
+ regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_CFG_REG,
+ IEP_GLOBAL_CFG_CNT_ENABLE,
+ IEP_GLOBAL_CFG_CNT_ENABLE);
+}
+
+static void icss_iep_disable(struct icss_iep *iep)
+{
+ regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_CFG_REG,
+ IEP_GLOBAL_CFG_CNT_ENABLE,
+ 0);
+}
+
+static void icss_iep_enable_shadow_mode(struct icss_iep *iep)
+{
+ u32 cycle_time;
+ int cmp;
+
+ cycle_time = iep->cycle_time_ns - iep->def_inc;
+
+ icss_iep_disable(iep);
+
+ /* disable shadow mode */
+ regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
+ IEP_CMP_CFG_SHADOW_EN, 0);
+
+ /* enable shadow mode */
+ regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
+ IEP_CMP_CFG_SHADOW_EN, IEP_CMP_CFG_SHADOW_EN);
+
+ /* clear counters */
+ icss_iep_set_counter(iep, 0);
+
+ /* clear overflow status */
+ regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_STATUS_REG,
+ IEP_GLOBAL_STATUS_CNT_OVF,
+ IEP_GLOBAL_STATUS_CNT_OVF);
+
+ /* clear compare status */
+ for (cmp = IEP_MIN_CMP; cmp < IEP_MAX_CMP; cmp++) {
+ regmap_update_bits(iep->map, ICSS_IEP_CMP_STAT_REG,
+ IEP_CMP_STATUS(cmp), IEP_CMP_STATUS(cmp));
+ }
+
+ /* enable reset counter on CMP0 event */
+ regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
+ IEP_CMP_CFG_CMP0_RST_CNT_EN,
+ IEP_CMP_CFG_CMP0_RST_CNT_EN);
+ /* enable compare */
+ regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
+ IEP_CMP_CFG_CMP_EN(0),
+ IEP_CMP_CFG_CMP_EN(0));
+
+ /* set CMP0 value to cycle time */
+ regmap_write(iep->map, ICSS_IEP_CMP0_REG0, cycle_time);
+ if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
+ regmap_write(iep->map, ICSS_IEP_CMP0_REG1, cycle_time);
+
+ icss_iep_set_counter(iep, 0);
+ icss_iep_enable(iep);
+}
+
+static void icss_iep_set_default_inc(struct icss_iep *iep, u8 def_inc)
+{
+ regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_CFG_REG,
+ IEP_GLOBAL_CFG_DEFAULT_INC_MASK,
+ def_inc << IEP_GLOBAL_CFG_DEFAULT_INC_SHIFT);
+}
+
+static void icss_iep_set_compensation_inc(struct icss_iep *iep, u16 compen_inc)
+{
+ struct device *dev = regmap_get_device(iep->map);
+
+ if (compen_inc > IEP_MAX_COMPEN_INC) {
+ dev_err(dev, "%s: too high compensation inc %d\n",
+ __func__, compen_inc);
+ compen_inc = IEP_MAX_COMPEN_INC;
+ }
+
+ regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_CFG_REG,
+ IEP_GLOBAL_CFG_COMPEN_INC_MASK,
+ compen_inc << IEP_GLOBAL_CFG_COMPEN_INC_SHIFT);
+}
+
+static void icss_iep_set_compensation_count(struct icss_iep *iep,
+ u32 compen_count)
+{
+ struct device *dev = regmap_get_device(iep->map);
+
+ if (compen_count > IEP_MAX_COMPEN_COUNT) {
+ dev_err(dev, "%s: too high compensation count %d\n",
+ __func__, compen_count);
+ compen_count = IEP_MAX_COMPEN_COUNT;
+ }
+
+ regmap_write(iep->map, ICSS_IEP_COMPEN_REG, compen_count);
+}
+
+static void icss_iep_set_slow_compensation_count(struct icss_iep *iep,
+ u32 compen_count)
+{
+ regmap_write(iep->map, ICSS_IEP_SLOW_COMPEN_REG, compen_count);
+}
+
+/* PTP PHC operations */
+static int icss_iep_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
+{
+ struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
+ s32 ppb = scaled_ppm_to_ppb(scaled_ppm);
+ u32 cyc_count;
+ u16 cmp_inc;
+
+ mutex_lock(&iep->ptp_clk_mutex);
+
+ /* ppb is amount of frequency we want to adjust in 1GHz (billion)
+ * e.g. 100ppb means we need to speed up clock by 100Hz
+ * i.e. at end of 1 second (1 billion ns) clock time, we should be
+ * counting 100 more ns.
+ * We use IEP slow compensation to achieve continuous freq. adjustment.
+ * There are 2 parts. Cycle time and adjustment per cycle.
+ * Simplest case would be 1 sec Cycle time. Then adjustment
+ * pre cycle would be (def_inc + ppb) value.
+ * Cycle time will have to be chosen based on how worse the ppb is.
+ * e.g. smaller the ppb, cycle time has to be large.
+ * The minimum adjustment we can do is +-1ns per cycle so let's
+ * reduce the cycle time to get 1ns per cycle adjustment.
+ * 1ppb = 1sec cycle time & 1ns adjust
+ * 1000ppb = 1/1000 cycle time & 1ns adjust per cycle
+ */
+
+ if (iep->cycle_time_ns)
+ iep->slow_cmp_inc = iep->clk_tick_time; /* 4ns adj per cycle */
+ else
+ iep->slow_cmp_inc = 1; /* 1ns adjust per cycle */
+
+ if (ppb < 0) {
+ iep->slow_cmp_inc = -iep->slow_cmp_inc;
+ ppb = -ppb;
+ }
+
+ cyc_count = NSEC_PER_SEC; /* 1s cycle time @1GHz */
+ cyc_count /= ppb; /* cycle time per ppb */
+
+ /* slow_cmp_count is decremented every clock cycle, e.g. @250MHz */
+ if (!iep->cycle_time_ns)
+ cyc_count /= iep->clk_tick_time;
+ iep->slow_cmp_count = cyc_count;
+
+ /* iep->clk_tick_time is def_inc */
+ cmp_inc = iep->clk_tick_time + iep->slow_cmp_inc;
+ icss_iep_set_compensation_inc(iep, cmp_inc);
+ icss_iep_set_slow_compensation_count(iep, iep->slow_cmp_count);
+
+ mutex_unlock(&iep->ptp_clk_mutex);
+
+ return 0;
+}
+
+static int icss_iep_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
+{
+ struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
+ s64 ns;
+
+ mutex_lock(&iep->ptp_clk_mutex);
+ if (iep->ops && iep->ops->adjtime) {
+ iep->ops->adjtime(iep->clockops_data, delta);
+ } else {
+ ns = icss_iep_gettime(iep, NULL);
+ ns += delta;
+ icss_iep_settime(iep, ns);
+ }
+ mutex_unlock(&iep->ptp_clk_mutex);
+
+ return 0;
+}
+
+static int icss_iep_ptp_gettimeex(struct ptp_clock_info *ptp,
+ struct timespec64 *ts,
+ struct ptp_system_timestamp *sts)
+{
+ struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
+ u64 ns;
+
+ mutex_lock(&iep->ptp_clk_mutex);
+ ns = icss_iep_gettime(iep, sts);
+ *ts = ns_to_timespec64(ns);
+ mutex_unlock(&iep->ptp_clk_mutex);
+
+ return 0;
+}
+
+static int icss_iep_ptp_settime(struct ptp_clock_info *ptp,
+ const struct timespec64 *ts)
+{
+ struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
+ u64 ns;
+
+ mutex_lock(&iep->ptp_clk_mutex);
+ ns = timespec64_to_ns(ts);
+ icss_iep_settime(iep, ns);
+ mutex_unlock(&iep->ptp_clk_mutex);
+
+ return 0;
+}
+
+static void icss_iep_update_to_next_boundary(struct icss_iep *iep, u64 start_ns)
+{
+ u64 ns, p_ns;
+ u32 offset;
+
+ ns = icss_iep_gettime(iep, NULL);
+ if (start_ns < ns)
+ start_ns = ns;
+ p_ns = iep->period;
+ /* Round up to next period boundary */
+ start_ns += p_ns - 1;
+ offset = do_div(start_ns, p_ns);
+ start_ns = start_ns * p_ns;
+ /* If it is too close to update, shift to next boundary */
+ if (p_ns - offset < 10)
+ start_ns += p_ns;
+
+ regmap_write(iep->map, ICSS_IEP_CMP1_REG0, lower_32_bits(start_ns));
+ if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
+ regmap_write(iep->map, ICSS_IEP_CMP1_REG1, upper_32_bits(start_ns));
+}
+
+static int icss_iep_perout_enable_hw(struct icss_iep *iep,
+ struct ptp_perout_request *req, int on)
+{
+ int ret;
+ u64 cmp;
+
+ if (iep->ops && iep->ops->perout_enable) {
+ ret = iep->ops->perout_enable(iep->clockops_data, req, on, &cmp);
+ if (ret)
+ return ret;
+
+ if (on) {
+ /* Configure CMP */
+ regmap_write(iep->map, ICSS_IEP_CMP1_REG0, lower_32_bits(cmp));
+ if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
+ regmap_write(iep->map, ICSS_IEP_CMP1_REG1, upper_32_bits(cmp));
+ /* Configure SYNC, 1ms pulse width */
+ regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG, 1000000);
+ regmap_write(iep->map, ICSS_IEP_SYNC0_PERIOD_REG, 0);
+ regmap_write(iep->map, ICSS_IEP_SYNC_START_REG, 0);
+ regmap_write(iep->map, ICSS_IEP_SYNC_CTRL_REG, 0); /* one-shot mode */
+ /* Enable CMP 1 */
+ regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
+ IEP_CMP_CFG_CMP_EN(1), IEP_CMP_CFG_CMP_EN(1));
+ } else {
+ /* Disable CMP 1 */
+ regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
+ IEP_CMP_CFG_CMP_EN(1), 0);
+
+ /* clear regs */
+ regmap_write(iep->map, ICSS_IEP_CMP1_REG0, 0);
+ if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
+ regmap_write(iep->map, ICSS_IEP_CMP1_REG1, 0);
+ }
+ } else {
+ if (on) {
+ u64 start_ns;
+
+ iep->period = ((u64)req->period.sec * NSEC_PER_SEC) +
+ req->period.nsec;
+ start_ns = ((u64)req->period.sec * NSEC_PER_SEC)
+ + req->period.nsec;
+ icss_iep_update_to_next_boundary(iep, start_ns);
+
+ /* Enable Sync in single shot mode */
+ regmap_write(iep->map, ICSS_IEP_SYNC_CTRL_REG,
+ IEP_SYNC_CTRL_SYNC_N_EN(0) | IEP_SYNC_CTRL_SYNC_EN);
+ /* Enable CMP 1 */
+ regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
+ IEP_CMP_CFG_CMP_EN(1), IEP_CMP_CFG_CMP_EN(1));
+ } else {
+ /* Disable CMP 1 */
+ regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
+ IEP_CMP_CFG_CMP_EN(1), 0);
+
+ /* clear CMP regs */
+ regmap_write(iep->map, ICSS_IEP_CMP1_REG0, 0);
+ if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
+ regmap_write(iep->map, ICSS_IEP_CMP1_REG1, 0);
+
+ /* Disable sync */
+ regmap_write(iep->map, ICSS_IEP_SYNC_CTRL_REG, 0);
+ }
+ }
+
+ return 0;
+}
+
+static int icss_iep_perout_enable(struct icss_iep *iep,
+ struct ptp_perout_request *req, int on)
+{
+ unsigned long flags;
+ int ret = 0;
+
+ mutex_lock(&iep->ptp_clk_mutex);
+
+ if (iep->pps_enabled) {
+ ret = -EBUSY;
+ goto exit;
+ }
+
+ if (iep->perout_enabled == !!on)
+ goto exit;
+
+ spin_lock_irqsave(&iep->irq_lock, flags);
+ ret = icss_iep_perout_enable_hw(iep, req, on);
+ if (!ret)
+ iep->perout_enabled = !!on;
+ spin_unlock_irqrestore(&iep->irq_lock, flags);
+
+exit:
+ mutex_unlock(&iep->ptp_clk_mutex);
+
+ return ret;
+}
+
+static int icss_iep_pps_enable(struct icss_iep *iep, int on)
+{
+ struct ptp_clock_request rq;
+ struct timespec64 ts;
+ unsigned long flags;
+ int ret = 0;
+ u64 ns;
+
+ mutex_lock(&iep->ptp_clk_mutex);
+
+ if (iep->perout_enabled) {
+ ret = -EBUSY;
+ goto exit;
+ }
+
+ if (iep->pps_enabled == !!on)
+ goto exit;
+
+ spin_lock_irqsave(&iep->irq_lock, flags);
+
+ rq.perout.index = 0;
+ if (on) {
+ ns = icss_iep_gettime(iep, NULL);
+ ts = ns_to_timespec64(ns);
+ rq.perout.period.sec = 1;
+ rq.perout.period.nsec = 0;
+ rq.perout.start.sec = ts.tv_sec + 2;
+ rq.perout.start.nsec = 0;
+ ret = icss_iep_perout_enable_hw(iep, &rq.perout, on);
+ } else {
+ ret = icss_iep_perout_enable_hw(iep, &rq.perout, on);
+ }
+
+ if (!ret)
+ iep->pps_enabled = !!on;
+
+ spin_unlock_irqrestore(&iep->irq_lock, flags);
+
+exit:
+ mutex_unlock(&iep->ptp_clk_mutex);
+
+ return ret;
+}
+
+static int icss_iep_extts_enable(struct icss_iep *iep, u32 index, int on)
+{
+ u32 val, cap, ret = 0;
+
+ mutex_lock(&iep->ptp_clk_mutex);
+
+ if (iep->ops && iep->ops->extts_enable) {
+ ret = iep->ops->extts_enable(iep->clockops_data, index, on);
+ goto exit;
+ }
+
+ if (((iep->latch_enable & BIT(index)) >> index) == on)
+ goto exit;
+
+ regmap_read(iep->map, ICSS_IEP_CAPTURE_CFG_REG, &val);
+ cap = IEP_CAP_CFG_CAP_ASYNC_EN(index) | IEP_CAP_CFG_CAPNR_1ST_EVENT_EN(index);
+ if (on) {
+ val |= cap;
+ iep->latch_enable |= BIT(index);
+ } else {
+ val &= ~cap;
+ iep->latch_enable &= ~BIT(index);
+ }
+ regmap_write(iep->map, ICSS_IEP_CAPTURE_CFG_REG, val);
+
+exit:
+ mutex_unlock(&iep->ptp_clk_mutex);
+
+ return ret;
+}
+
+static int icss_iep_ptp_enable(struct ptp_clock_info *ptp,
+ struct ptp_clock_request *rq, int on)
+{
+ struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
+
+ switch (rq->type) {
+ case PTP_CLK_REQ_PEROUT:
+ return icss_iep_perout_enable(iep, &rq->perout, on);
+ case PTP_CLK_REQ_PPS:
+ return icss_iep_pps_enable(iep, on);
+ case PTP_CLK_REQ_EXTTS:
+ return icss_iep_extts_enable(iep, rq->extts.index, on);
+ default:
+ break;
+ }
+
+ return -EOPNOTSUPP;
+}
+
+static struct ptp_clock_info icss_iep_ptp_info = {
+ .owner = THIS_MODULE,
+ .name = "ICSS IEP timer",
+ .max_adj = 10000000,
+ .adjfine = icss_iep_ptp_adjfine,
+ .adjtime = icss_iep_ptp_adjtime,
+ .gettimex64 = icss_iep_ptp_gettimeex,
+ .settime64 = icss_iep_ptp_settime,
+ .enable = icss_iep_ptp_enable,
+};
+
+struct icss_iep *icss_iep_get_idx(struct device_node *np, int idx)
+{
+ struct platform_device *pdev;
+ struct device_node *iep_np;
+ struct icss_iep *iep;
+
+ iep_np = of_parse_phandle(np, "ti,iep", idx);
+ if (!iep_np || !of_device_is_available(iep_np))
+ return ERR_PTR(-ENODEV);
+
+ pdev = of_find_device_by_node(iep_np);
+ of_node_put(iep_np);
+
+ if (!pdev)
+ /* probably IEP not yet probed */
+ return ERR_PTR(-EPROBE_DEFER);
+
+ iep = platform_get_drvdata(pdev);
+ if (!iep)
+ return ERR_PTR(-EPROBE_DEFER);
+
+ device_lock(iep->dev);
+ if (iep->client_np) {
+ device_unlock(iep->dev);
+ dev_err(iep->dev, "IEP is already acquired by %s",
+ iep->client_np->name);
+ return ERR_PTR(-EBUSY);
+ }
+ iep->client_np = np;
+ device_unlock(iep->dev);
+ get_device(iep->dev);
+
+ return iep;
+}
+EXPORT_SYMBOL_GPL(icss_iep_get_idx);
+
+struct icss_iep *icss_iep_get(struct device_node *np)
+{
+ return icss_iep_get_idx(np, 0);
+}
+EXPORT_SYMBOL_GPL(icss_iep_get);
+
+void icss_iep_put(struct icss_iep *iep)
+{
+ device_lock(iep->dev);
+ iep->client_np = NULL;
+ device_unlock(iep->dev);
+ put_device(iep->dev);
+}
+EXPORT_SYMBOL_GPL(icss_iep_put);
+
+int icss_iep_init(struct icss_iep *iep, const struct icss_iep_clockops *clkops,
+ void *clockops_data, u32 cycle_time_ns)
+{
+ int ret = 0;
+
+ iep->cycle_time_ns = cycle_time_ns;
+ iep->clk_tick_time = iep->def_inc;
+ iep->ops = clkops;
+ iep->clockops_data = clockops_data;
+ icss_iep_set_default_inc(iep, iep->def_inc);
+ icss_iep_set_compensation_inc(iep, iep->def_inc);
+ icss_iep_set_compensation_count(iep, 0);
+ regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG, iep->refclk_freq / 10); /* 100 ms pulse */
+ regmap_write(iep->map, ICSS_IEP_SYNC0_PERIOD_REG, 0);
+ if (iep->plat_data->flags & ICSS_IEP_SLOW_COMPEN_REG_SUPPORT)
+ icss_iep_set_slow_compensation_count(iep, 0);
+
+ if (!(iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT) ||
+ !(iep->plat_data->flags & ICSS_IEP_SLOW_COMPEN_REG_SUPPORT))
+ goto skip_perout;
+
+ if (iep->ops && iep->ops->perout_enable) {
+ iep->ptp_info.n_per_out = 1;
+ iep->ptp_info.pps = 1;
+ }
+
+ if (iep->ops && iep->ops->extts_enable)
+ iep->ptp_info.n_ext_ts = 2;
+
+skip_perout:
+ if (cycle_time_ns)
+ icss_iep_enable_shadow_mode(iep);
+ else
+ icss_iep_enable(iep);
+ icss_iep_settime(iep, ktime_get_real_ns());
+
+ iep->ptp_clock = ptp_clock_register(&iep->ptp_info, iep->dev);
+ if (IS_ERR(iep->ptp_clock)) {
+ ret = PTR_ERR(iep->ptp_clock);
+ iep->ptp_clock = NULL;
+ dev_err(iep->dev, "Failed to register ptp clk %d\n", ret);
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(icss_iep_init);
+
+int icss_iep_exit(struct icss_iep *iep)
+{
+ if (iep->ptp_clock) {
+ ptp_clock_unregister(iep->ptp_clock);
+ iep->ptp_clock = NULL;
+ }
+ icss_iep_disable(iep);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(icss_iep_exit);
+
+static int icss_iep_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct icss_iep *iep;
+ struct clk *iep_clk;
+
+ iep = devm_kzalloc(dev, sizeof(*iep), GFP_KERNEL);
+ if (!iep)
+ return -ENOMEM;
+
+ iep->dev = dev;
+ iep->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(iep->base))
+ return -ENODEV;
+
+ iep_clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(iep_clk))
+ return PTR_ERR(iep_clk);
+
+ iep->refclk_freq = clk_get_rate(iep_clk);
+
+ iep->def_inc = NSEC_PER_SEC / iep->refclk_freq; /* ns per clock tick */
+ if (iep->def_inc > IEP_MAX_DEF_INC) {
+ dev_err(dev, "Failed to set def_inc %d. IEP_clock is too slow to be supported\n",
+ iep->def_inc);
+ return -EINVAL;
+ }
+
+ iep->plat_data = device_get_match_data(dev);
+ if (!iep->plat_data)
+ return -EINVAL;
+
+ iep->map = devm_regmap_init(dev, NULL, iep, iep->plat_data->config);
+ if (IS_ERR(iep->map)) {
+ dev_err(dev, "Failed to create regmap for IEP %ld\n",
+ PTR_ERR(iep->map));
+ return PTR_ERR(iep->map);
+ }
+
+ iep->ptp_info = icss_iep_ptp_info;
+ mutex_init(&iep->ptp_clk_mutex);
+ spin_lock_init(&iep->irq_lock);
+ dev_set_drvdata(dev, iep);
+ icss_iep_disable(iep);
+
+ return 0;
+}
+
+static bool am654_icss_iep_valid_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case ICSS_IEP_GLOBAL_CFG_REG ... ICSS_IEP_SYNC_START_REG:
+ return true;
+ default:
+ return false;
+ }
+
+ return false;
+}
+
+static int icss_iep_regmap_write(void *context, unsigned int reg,
+ unsigned int val)
+{
+ struct icss_iep *iep = context;
+
+ writel(val, iep->base + iep->plat_data->reg_offs[reg]);
+
+ return 0;
+}
+
+static int icss_iep_regmap_read(void *context, unsigned int reg,
+ unsigned int *val)
+{
+ struct icss_iep *iep = context;
+
+ *val = readl(iep->base + iep->plat_data->reg_offs[reg]);
+
+ return 0;
+}
+
+static struct regmap_config am654_icss_iep_regmap_config = {
+ .name = "icss iep",
+ .reg_stride = 1,
+ .reg_write = icss_iep_regmap_write,
+ .reg_read = icss_iep_regmap_read,
+ .writeable_reg = am654_icss_iep_valid_reg,
+ .readable_reg = am654_icss_iep_valid_reg,
+ .fast_io = 1,
+};
+
+static const struct icss_iep_plat_data am654_icss_iep_plat_data = {
+ .flags = ICSS_IEP_64BIT_COUNTER_SUPPORT |
+ ICSS_IEP_SLOW_COMPEN_REG_SUPPORT |
+ ICSS_IEP_SHADOW_MODE_SUPPORT,
+ .reg_offs = {
+ [ICSS_IEP_GLOBAL_CFG_REG] = 0x00,
+ [ICSS_IEP_COMPEN_REG] = 0x08,
+ [ICSS_IEP_SLOW_COMPEN_REG] = 0x0C,
+ [ICSS_IEP_COUNT_REG0] = 0x10,
+ [ICSS_IEP_COUNT_REG1] = 0x14,
+ [ICSS_IEP_CAPTURE_CFG_REG] = 0x18,
+ [ICSS_IEP_CAPTURE_STAT_REG] = 0x1c,
+
+ [ICSS_IEP_CAP6_RISE_REG0] = 0x50,
+ [ICSS_IEP_CAP6_RISE_REG1] = 0x54,
+
+ [ICSS_IEP_CAP7_RISE_REG0] = 0x60,
+ [ICSS_IEP_CAP7_RISE_REG1] = 0x64,
+
+ [ICSS_IEP_CMP_CFG_REG] = 0x70,
+ [ICSS_IEP_CMP_STAT_REG] = 0x74,
+ [ICSS_IEP_CMP0_REG0] = 0x78,
+ [ICSS_IEP_CMP0_REG1] = 0x7c,
+ [ICSS_IEP_CMP1_REG0] = 0x80,
+ [ICSS_IEP_CMP1_REG1] = 0x84,
+
+ [ICSS_IEP_CMP8_REG0] = 0xc0,
+ [ICSS_IEP_CMP8_REG1] = 0xc4,
+ [ICSS_IEP_SYNC_CTRL_REG] = 0x180,
+ [ICSS_IEP_SYNC0_STAT_REG] = 0x188,
+ [ICSS_IEP_SYNC1_STAT_REG] = 0x18c,
+ [ICSS_IEP_SYNC_PWIDTH_REG] = 0x190,
+ [ICSS_IEP_SYNC0_PERIOD_REG] = 0x194,
+ [ICSS_IEP_SYNC1_DELAY_REG] = 0x198,
+ [ICSS_IEP_SYNC_START_REG] = 0x19c,
+ },
+ .config = &am654_icss_iep_regmap_config,
+};
+
+static const struct of_device_id icss_iep_of_match[] = {
+ {
+ .compatible = "ti,am654-icss-iep",
+ .data = &am654_icss_iep_plat_data,
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, icss_iep_of_match);
+
+static struct platform_driver icss_iep_driver = {
+ .driver = {
+ .name = "icss-iep",
+ .of_match_table = icss_iep_of_match,
+ },
+ .probe = icss_iep_probe,
+};
+module_platform_driver(icss_iep_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("TI ICSS IEP driver");
+MODULE_AUTHOR("Roger Quadros <[email protected]>");
+MODULE_AUTHOR("Md Danish Anwar <[email protected]>");
diff --git a/drivers/net/ethernet/ti/icssg/icss_iep.h b/drivers/net/ethernet/ti/icssg/icss_iep.h
new file mode 100644
index 000000000000..9eee44ae4990
--- /dev/null
+++ b/drivers/net/ethernet/ti/icssg/icss_iep.h
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Texas Instruments ICSSG Industrial Ethernet Peripheral (IEP) Driver
+ *
+ * Copyright (C) 2023 Texas Instruments Incorporated - https://www.ti.com/
+ *
+ */
+
+#ifndef __NET_TI_ICSS_IEP_H
+#define __NET_TI_ICSS_IEP_H
+
+#include <linux/mutex.h>
+#include <linux/ptp_clock_kernel.h>
+#include <linux/regmap.h>
+
+struct icss_iep;
+
+/* Firmware specific clock operations */
+struct icss_iep_clockops {
+ void (*settime)(void *clockops_data, u64 ns);
+ void (*adjtime)(void *clockops_data, s64 delta);
+ u64 (*gettime)(void *clockops_data, struct ptp_system_timestamp *sts);
+ int (*perout_enable)(void *clockops_data,
+ struct ptp_perout_request *req, int on,
+ u64 *cmp);
+ int (*extts_enable)(void *clockops_data, u32 index, int on);
+};
+
+struct icss_iep *icss_iep_get(struct device_node *np);
+struct icss_iep *icss_iep_get_idx(struct device_node *np, int idx);
+void icss_iep_put(struct icss_iep *iep);
+int icss_iep_init(struct icss_iep *iep, const struct icss_iep_clockops *clkops,
+ void *clockops_data, u32 cycle_time_ns);
+int icss_iep_exit(struct icss_iep *iep);
+int icss_iep_get_count_low(struct icss_iep *iep);
+int icss_iep_get_count_hi(struct icss_iep *iep);
+int icss_iep_get_ptp_clock_idx(struct icss_iep *iep);
+
+#endif /* __NET_TI_ICSS_IEP_H */
--
2.34.1



2023-08-15 10:35:54

by Roger Quadros

[permalink] [raw]
Subject: Re: [PATCH v4 3/5] net: ti: icss-iep: Add IEP driver



On 15/08/2023 13:07, Anwar, Md Danish wrote:
> Hi Roger,
>
> On 8/15/2023 3:11 PM, Roger Quadros wrote:
>> Hi Danish,
>>
>> On 14/08/2023 13:08, MD Danish Anwar wrote:
>>> From: Roger Quadros <[email protected]>
>>>
>>> Add a driver for Industrial Ethernet Peripheral (IEP) block of PRUSS to
>>> support timestamping of ethernet packets and thus support PTP and PPS
>>> for PRU ethernet ports.
>>>
>>> Signed-off-by: Roger Quadros <[email protected]>
>>> Signed-off-by: Lokesh Vutla <[email protected]>
>>> Signed-off-by: Murali Karicheri <[email protected]>
>>> Signed-off-by: Vignesh Raghavendra <[email protected]>
>>> Signed-off-by: MD Danish Anwar <[email protected]>
>>> ---
>>>   drivers/net/ethernet/ti/Kconfig          |  11 +
>>>   drivers/net/ethernet/ti/Makefile         |   1 +
>>>   drivers/net/ethernet/ti/icssg/icss_iep.c | 921 +++++++++++++++++++++++
>>>   drivers/net/ethernet/ti/icssg/icss_iep.h |  38 +
>>>   4 files changed, 971 insertions(+)
>>>   create mode 100644 drivers/net/ethernet/ti/icssg/icss_iep.c
>>>   create mode 100644 drivers/net/ethernet/ti/icssg/icss_iep.h
>>>
>>> diff --git a/drivers/net/ethernet/ti/Kconfig b/drivers/net/ethernet/ti/Kconfig
>>> index 63e510b6860f..1af5a90720ec 100644
>>> --- a/drivers/net/ethernet/ti/Kconfig
>>> +++ b/drivers/net/ethernet/ti/Kconfig
>>> @@ -196,4 +196,15 @@ config TI_ICSSG_PRUETH
>>>         to support the Ethernet operation. Currently, it supports Ethernet
>>>         with 1G and 100M link speed.
>>>   +config TI_ICSS_IEP
>>> +    tristate "TI PRU ICSS IEP driver"
>>> +    depends on TI_PRUSS
>>> +    default TI_PRUSS
>>> +    help
>>> +      This driver enables support for the PRU-ICSS Industrial Ethernet
>>> +      Peripheral within a PRU-ICSS subsystem present on various TI SoCs.
>>> +
>>> +      To compile this driver as a module, choose M here. The module
>>> +      will be called icss_iep.
>>> +
>>>   endif # NET_VENDOR_TI
>>> diff --git a/drivers/net/ethernet/ti/Makefile b/drivers/net/ethernet/ti/Makefile
>>> index 9176d79c36e1..34fd7a716ba6 100644
>>> --- a/drivers/net/ethernet/ti/Makefile
>>> +++ b/drivers/net/ethernet/ti/Makefile
>>> @@ -38,3 +38,4 @@ icssg-prueth-y := k3-cppi-desc-pool.o \
>>>             icssg/icssg_mii_cfg.o \
>>>             icssg/icssg_stats.o \
>>>             icssg/icssg_ethtool.o
>>> +obj-$(CONFIG_TI_ICSS_IEP) += icssg/icss_iep.o
>>> diff --git a/drivers/net/ethernet/ti/icssg/icss_iep.c b/drivers/net/ethernet/ti/icssg/icss_iep.c
>>> new file mode 100644
>>> index 000000000000..d123b8ba3f31
>>> --- /dev/null
>>> +++ b/drivers/net/ethernet/ti/icssg/icss_iep.c
>>> @@ -0,0 +1,921 @@
>>> +// SPDX-License-Identifier: GPL-2.0
>>> +
>>> +/* Texas Instruments ICSSG Industrial Ethernet Peripheral (IEP) Driver
>>> + *
>>> + * Copyright (C) 2023 Texas Instruments Incorporated - https://www.ti.com
>>> + *
>>> + */
>>> +
>>> +#include <linux/bitops.h>
>>> +#include <linux/clk.h>
>>> +#include <linux/err.h>
>>> +#include <linux/io.h>
>>> +#include <linux/module.h>
>>> +#include <linux/of.h>
>>> +#include <linux/of_platform.h>
>>> +#include <linux/platform_device.h>
>>> +#include <linux/timekeeping.h>
>>> +#include <linux/interrupt.h>
>>> +#include <linux/of_irq.h>
>>> +
>>> +#include "icss_iep.h"
>>> +
>>> +#define IEP_MAX_DEF_INC        0xf
>>> +#define IEP_MAX_COMPEN_INC        0xfff
>>> +#define IEP_MAX_COMPEN_COUNT    0xffffff
>>> +
>>> +#define IEP_GLOBAL_CFG_CNT_ENABLE    BIT(0)
>>> +#define IEP_GLOBAL_CFG_DEFAULT_INC_MASK        GENMASK(7, 4)
>>> +#define IEP_GLOBAL_CFG_DEFAULT_INC_SHIFT    4
>>> +#define IEP_GLOBAL_CFG_COMPEN_INC_MASK        GENMASK(19, 8)
>>> +#define IEP_GLOBAL_CFG_COMPEN_INC_SHIFT        8
>>> +
>>> +#define IEP_GLOBAL_STATUS_CNT_OVF    BIT(0)
>>> +
>>> +#define IEP_CMP_CFG_SHADOW_EN        BIT(17)
>>> +#define IEP_CMP_CFG_CMP0_RST_CNT_EN    BIT(0)
>>> +#define IEP_CMP_CFG_CMP_EN(cmp)        (GENMASK(16, 1) & (1 << ((cmp) + 1)))
>>> +
>>> +#define IEP_CMP_STATUS(cmp)        (1 << (cmp))
>>> +
>>> +#define IEP_SYNC_CTRL_SYNC_EN        BIT(0)
>>> +#define IEP_SYNC_CTRL_SYNC_N_EN(n)    (GENMASK(2, 1) & (BIT(1) << (n)))
>>> +
>>> +#define IEP_MIN_CMP    0
>>> +#define IEP_MAX_CMP    15
>>> +
>>> +#define ICSS_IEP_64BIT_COUNTER_SUPPORT        BIT(0)
>>> +#define ICSS_IEP_SLOW_COMPEN_REG_SUPPORT    BIT(1)
>>> +#define ICSS_IEP_SHADOW_MODE_SUPPORT        BIT(2)
>>> +
>>> +#define LATCH_INDEX(ts_index)            ((ts_index) + 6)
>>> +#define IEP_CAP_CFG_CAPNR_1ST_EVENT_EN(n)    BIT(LATCH_INDEX(n))
>>> +#define IEP_CAP_CFG_CAP_ASYNC_EN(n)        BIT(LATCH_INDEX(n) + 10)
>>> +
>>> +enum {
>>> +    ICSS_IEP_GLOBAL_CFG_REG,
>>> +    ICSS_IEP_GLOBAL_STATUS_REG,
>>> +    ICSS_IEP_COMPEN_REG,
>>> +    ICSS_IEP_SLOW_COMPEN_REG,
>>> +    ICSS_IEP_COUNT_REG0,
>>> +    ICSS_IEP_COUNT_REG1,
>>> +    ICSS_IEP_CAPTURE_CFG_REG,
>>> +    ICSS_IEP_CAPTURE_STAT_REG,
>>> +
>>> +    ICSS_IEP_CAP6_RISE_REG0,
>>> +    ICSS_IEP_CAP6_RISE_REG1,
>>> +
>>> +    ICSS_IEP_CAP7_RISE_REG0,
>>> +    ICSS_IEP_CAP7_RISE_REG1,
>>> +
>>> +    ICSS_IEP_CMP_CFG_REG,
>>> +    ICSS_IEP_CMP_STAT_REG,
>>> +    ICSS_IEP_CMP0_REG0,
>>> +    ICSS_IEP_CMP0_REG1,
>>> +    ICSS_IEP_CMP1_REG0,
>>> +    ICSS_IEP_CMP1_REG1,
>>> +
>>> +    ICSS_IEP_CMP8_REG0,
>>> +    ICSS_IEP_CMP8_REG1,
>>> +    ICSS_IEP_SYNC_CTRL_REG,
>>> +    ICSS_IEP_SYNC0_STAT_REG,
>>> +    ICSS_IEP_SYNC1_STAT_REG,
>>> +    ICSS_IEP_SYNC_PWIDTH_REG,
>>> +    ICSS_IEP_SYNC0_PERIOD_REG,
>>> +    ICSS_IEP_SYNC1_DELAY_REG,
>>> +    ICSS_IEP_SYNC_START_REG,
>>> +    ICSS_IEP_MAX_REGS,
>>> +};
>>> +
>>> +/**
>>> + * struct icss_iep_plat_data - Plat data to handle SoC variants
>>> + * @config: Regmap configuration data
>>> + * @reg_offs: register offsets to capture offset differences across SoCs
>>> + * @flags: Flags to represent IEP properties
>>> + */
>>> +struct icss_iep_plat_data {
>>> +    struct regmap_config *config;
>>> +    u32 reg_offs[ICSS_IEP_MAX_REGS];
>>> +    u32 flags;
>>> +};
>>> +
>>> +struct icss_iep {
>>> +    struct device *dev;
>>> +    void __iomem *base;
>>> +    const struct icss_iep_plat_data *plat_data;
>>> +    struct regmap *map;
>>> +    struct device_node *client_np;
>>> +    unsigned long refclk_freq;
>>> +    int clk_tick_time;    /* one refclk tick time in ns */
>>> +    struct ptp_clock_info ptp_info;
>>> +    struct ptp_clock *ptp_clock;
>>> +    struct mutex ptp_clk_mutex;    /* PHC access serializer */
>>> +    spinlock_t irq_lock; /* CMP IRQ vs icss_iep_ptp_enable access */
>>> +    u32 def_inc;
>>> +    s16 slow_cmp_inc;
>>> +    u32 slow_cmp_count;
>>> +    const struct icss_iep_clockops *ops;
>>> +    void *clockops_data;
>>> +    u32 cycle_time_ns;
>>> +    u32 perout_enabled;
>>> +    bool pps_enabled;
>>> +    int cap_cmp_irq;
>>> +    u64 period;
>>> +    u32 latch_enable;
>>> +};
>>> +
>>
>> Where is the comment you agreed to add on why we are using readl/writel
>> instead of regmap in certain areas?
>>
>
> We agreed to add comment on why we are using readl/writel instead of regmap in the documentation of the readl / writel helper APIs (icss_iep_readl / writel ). But Andrew asked me to drop those helper APIs, so I dropped them. Now no helper APIs are there and we are directly using readl / writel in total 8 places. Previously with the helper APIs, there was a way to document the use of readl / writel before the declaration of heper APIs. Now with no helper APIs, I couldn't find a good place to add this documentation as all 8 instances using readl / writel seems similar. So I dropped it.

Please limit your reply to around 80 columns wide.
https://people.kernel.org/tglx/notes-about-netiquette

You don't have to put the comment everywhere you use readl/writel
but you need to put it at least once hopefully just before icss_iep_gettime()
so future readers of this code know the reasoning why we are not
using regmap API throughout.

>
>>> +/**
>>> + * icss_iep_get_count_hi() - Get the upper 32 bit IEP counter
>>> + * @iep: Pointer to structure representing IEP.
>>> + *
>>> + * Return: upper 32 bit IEP counter
>>> + */
>>> +int icss_iep_get_count_hi(struct icss_iep *iep)
>>> +{
>>> +    u32 val = 0;
>>> +
>>> +    if (iep && (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT))
>>> +        val = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG1]);
>>> +
>>> +    return val;
>>> +}
>>> +EXPORT_SYMBOL_GPL(icss_iep_get_count_hi);
>>> +
>>> +/**
>>> + * icss_iep_get_count_low() - Get the lower 32 bit IEP counter
>>> + * @iep: Pointer to structure representing IEP.
>>> + *
>>> + * Return: lower 32 bit IEP counter
>>> + */
>>> +int icss_iep_get_count_low(struct icss_iep *iep)
>>> +{
>>> +    u32 val = 0;
>>> +
>>> +    if (iep)
>>> +        val = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG0]);
>>> +
>>> +    return val;
>>> +}
>>> +EXPORT_SYMBOL_GPL(icss_iep_get_count_low);
>>> +
>>> +/**
>>> + * icss_iep_get_ptp_clock_idx() - Get PTP clock index using IEP driver
>>> + * @iep: Pointer to structure representing IEP.
>>> + *
>>> + * Return: PTP clock index, -1 if not registered
>>> + */
>>> +int icss_iep_get_ptp_clock_idx(struct icss_iep *iep)
>>> +{
>>> +    if (!iep || !iep->ptp_clock)
>>> +        return -1;
>>> +    return ptp_clock_index(iep->ptp_clock);
>>> +}
>>> +EXPORT_SYMBOL_GPL(icss_iep_get_ptp_clock_idx);
>>> +
>>> +static void icss_iep_set_counter(struct icss_iep *iep, u64 ns)
>>> +{
>>> +    if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
>>> +        writel(upper_32_bits(ns), iep->base +
>>> +               iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG1]);
>>> +    writel(upper_32_bits(ns), iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG0]);
>>> +}
>>> +
>>> +static void icss_iep_update_to_next_boundary(struct icss_iep *iep, u64 start_ns);
>>> +
>>> +static void icss_iep_settime(struct icss_iep *iep, u64 ns)
>>> +{
>>> +    unsigned long flags;
>>> +
>>> +    if (iep->ops && iep->ops->settime) {
>>> +        iep->ops->settime(iep->clockops_data, ns);
>>> +        return;
>>> +    }
>>> +
>>> +    spin_lock_irqsave(&iep->irq_lock, flags);
>>> +    if (iep->pps_enabled || iep->perout_enabled)
>>> +        writel(0, iep->base + iep->plat_data->reg_offs[ICSS_IEP_SYNC_CTRL_REG]);
>>> +
>>> +    icss_iep_set_counter(iep, ns);
>>> +
>>> +    if (iep->pps_enabled || iep->perout_enabled) {
>>> +        icss_iep_update_to_next_boundary(iep, ns);
>>> +        writel(IEP_SYNC_CTRL_SYNC_N_EN(0) | IEP_SYNC_CTRL_SYNC_EN,
>>> +               iep->base + iep->plat_data->reg_offs[ICSS_IEP_SYNC_CTRL_REG]);
>>> +    }
>>> +    spin_unlock_irqrestore(&iep->irq_lock, flags);
>>> +}
>>> +
>>> +static u64 icss_iep_gettime(struct icss_iep *iep,
>>> +                struct ptp_system_timestamp *sts)
>>> +{
>>> +    u32 ts_hi = 0, ts_lo;
>>> +    unsigned long flags;
>>> +
>>> +    if (iep->ops && iep->ops->gettime)
>>> +        return iep->ops->gettime(iep->clockops_data, sts);
>>> +
>>> +    /* use local_irq_x() to make it work for both RT/non-RT */
>>> +    local_irq_save(flags);
>>> +
>>> +    /* no need to play with hi-lo, hi is latched when lo is read */
>>> +    ptp_read_system_prets(sts);
>>> +    ts_lo = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG0]);
>>> +    ptp_read_system_postts(sts);
>>> +    if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
>>> +        ts_hi = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG1]);
>>> +
>>> +    local_irq_restore(flags);
>>> +
>>> +    return (u64)ts_lo | (u64)ts_hi << 32;
>>> +}
>>> +
>>> +static void icss_iep_enable(struct icss_iep *iep)
>>> +{
>>> +    regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_CFG_REG,
>>> +               IEP_GLOBAL_CFG_CNT_ENABLE,
>>> +               IEP_GLOBAL_CFG_CNT_ENABLE);
>>> +}
>>> +
>> <snip>
>>
>

--
cheers,
-roger

2023-08-15 16:30:43

by Roger Quadros

[permalink] [raw]
Subject: Re: [PATCH v4 3/5] net: ti: icss-iep: Add IEP driver

Hi Danish,

On 14/08/2023 13:08, MD Danish Anwar wrote:
> From: Roger Quadros <[email protected]>
>
> Add a driver for Industrial Ethernet Peripheral (IEP) block of PRUSS to
> support timestamping of ethernet packets and thus support PTP and PPS
> for PRU ethernet ports.
>
> Signed-off-by: Roger Quadros <[email protected]>
> Signed-off-by: Lokesh Vutla <[email protected]>
> Signed-off-by: Murali Karicheri <[email protected]>
> Signed-off-by: Vignesh Raghavendra <[email protected]>
> Signed-off-by: MD Danish Anwar <[email protected]>
> ---
> drivers/net/ethernet/ti/Kconfig | 11 +
> drivers/net/ethernet/ti/Makefile | 1 +
> drivers/net/ethernet/ti/icssg/icss_iep.c | 921 +++++++++++++++++++++++
> drivers/net/ethernet/ti/icssg/icss_iep.h | 38 +
> 4 files changed, 971 insertions(+)
> create mode 100644 drivers/net/ethernet/ti/icssg/icss_iep.c
> create mode 100644 drivers/net/ethernet/ti/icssg/icss_iep.h
>
> diff --git a/drivers/net/ethernet/ti/Kconfig b/drivers/net/ethernet/ti/Kconfig
> index 63e510b6860f..1af5a90720ec 100644
> --- a/drivers/net/ethernet/ti/Kconfig
> +++ b/drivers/net/ethernet/ti/Kconfig
> @@ -196,4 +196,15 @@ config TI_ICSSG_PRUETH
> to support the Ethernet operation. Currently, it supports Ethernet
> with 1G and 100M link speed.
>
> +config TI_ICSS_IEP
> + tristate "TI PRU ICSS IEP driver"
> + depends on TI_PRUSS
> + default TI_PRUSS
> + help
> + This driver enables support for the PRU-ICSS Industrial Ethernet
> + Peripheral within a PRU-ICSS subsystem present on various TI SoCs.
> +
> + To compile this driver as a module, choose M here. The module
> + will be called icss_iep.
> +
> endif # NET_VENDOR_TI
> diff --git a/drivers/net/ethernet/ti/Makefile b/drivers/net/ethernet/ti/Makefile
> index 9176d79c36e1..34fd7a716ba6 100644
> --- a/drivers/net/ethernet/ti/Makefile
> +++ b/drivers/net/ethernet/ti/Makefile
> @@ -38,3 +38,4 @@ icssg-prueth-y := k3-cppi-desc-pool.o \
> icssg/icssg_mii_cfg.o \
> icssg/icssg_stats.o \
> icssg/icssg_ethtool.o
> +obj-$(CONFIG_TI_ICSS_IEP) += icssg/icss_iep.o
> diff --git a/drivers/net/ethernet/ti/icssg/icss_iep.c b/drivers/net/ethernet/ti/icssg/icss_iep.c
> new file mode 100644
> index 000000000000..d123b8ba3f31
> --- /dev/null
> +++ b/drivers/net/ethernet/ti/icssg/icss_iep.c
> @@ -0,0 +1,921 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +/* Texas Instruments ICSSG Industrial Ethernet Peripheral (IEP) Driver
> + *
> + * Copyright (C) 2023 Texas Instruments Incorporated - https://www.ti.com
> + *
> + */
> +
> +#include <linux/bitops.h>
> +#include <linux/clk.h>
> +#include <linux/err.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_platform.h>
> +#include <linux/platform_device.h>
> +#include <linux/timekeeping.h>
> +#include <linux/interrupt.h>
> +#include <linux/of_irq.h>
> +
> +#include "icss_iep.h"
> +
> +#define IEP_MAX_DEF_INC 0xf
> +#define IEP_MAX_COMPEN_INC 0xfff
> +#define IEP_MAX_COMPEN_COUNT 0xffffff
> +
> +#define IEP_GLOBAL_CFG_CNT_ENABLE BIT(0)
> +#define IEP_GLOBAL_CFG_DEFAULT_INC_MASK GENMASK(7, 4)
> +#define IEP_GLOBAL_CFG_DEFAULT_INC_SHIFT 4
> +#define IEP_GLOBAL_CFG_COMPEN_INC_MASK GENMASK(19, 8)
> +#define IEP_GLOBAL_CFG_COMPEN_INC_SHIFT 8
> +
> +#define IEP_GLOBAL_STATUS_CNT_OVF BIT(0)
> +
> +#define IEP_CMP_CFG_SHADOW_EN BIT(17)
> +#define IEP_CMP_CFG_CMP0_RST_CNT_EN BIT(0)
> +#define IEP_CMP_CFG_CMP_EN(cmp) (GENMASK(16, 1) & (1 << ((cmp) + 1)))
> +
> +#define IEP_CMP_STATUS(cmp) (1 << (cmp))
> +
> +#define IEP_SYNC_CTRL_SYNC_EN BIT(0)
> +#define IEP_SYNC_CTRL_SYNC_N_EN(n) (GENMASK(2, 1) & (BIT(1) << (n)))
> +
> +#define IEP_MIN_CMP 0
> +#define IEP_MAX_CMP 15
> +
> +#define ICSS_IEP_64BIT_COUNTER_SUPPORT BIT(0)
> +#define ICSS_IEP_SLOW_COMPEN_REG_SUPPORT BIT(1)
> +#define ICSS_IEP_SHADOW_MODE_SUPPORT BIT(2)
> +
> +#define LATCH_INDEX(ts_index) ((ts_index) + 6)
> +#define IEP_CAP_CFG_CAPNR_1ST_EVENT_EN(n) BIT(LATCH_INDEX(n))
> +#define IEP_CAP_CFG_CAP_ASYNC_EN(n) BIT(LATCH_INDEX(n) + 10)
> +
> +enum {
> + ICSS_IEP_GLOBAL_CFG_REG,
> + ICSS_IEP_GLOBAL_STATUS_REG,
> + ICSS_IEP_COMPEN_REG,
> + ICSS_IEP_SLOW_COMPEN_REG,
> + ICSS_IEP_COUNT_REG0,
> + ICSS_IEP_COUNT_REG1,
> + ICSS_IEP_CAPTURE_CFG_REG,
> + ICSS_IEP_CAPTURE_STAT_REG,
> +
> + ICSS_IEP_CAP6_RISE_REG0,
> + ICSS_IEP_CAP6_RISE_REG1,
> +
> + ICSS_IEP_CAP7_RISE_REG0,
> + ICSS_IEP_CAP7_RISE_REG1,
> +
> + ICSS_IEP_CMP_CFG_REG,
> + ICSS_IEP_CMP_STAT_REG,
> + ICSS_IEP_CMP0_REG0,
> + ICSS_IEP_CMP0_REG1,
> + ICSS_IEP_CMP1_REG0,
> + ICSS_IEP_CMP1_REG1,
> +
> + ICSS_IEP_CMP8_REG0,
> + ICSS_IEP_CMP8_REG1,
> + ICSS_IEP_SYNC_CTRL_REG,
> + ICSS_IEP_SYNC0_STAT_REG,
> + ICSS_IEP_SYNC1_STAT_REG,
> + ICSS_IEP_SYNC_PWIDTH_REG,
> + ICSS_IEP_SYNC0_PERIOD_REG,
> + ICSS_IEP_SYNC1_DELAY_REG,
> + ICSS_IEP_SYNC_START_REG,
> + ICSS_IEP_MAX_REGS,
> +};
> +
> +/**
> + * struct icss_iep_plat_data - Plat data to handle SoC variants
> + * @config: Regmap configuration data
> + * @reg_offs: register offsets to capture offset differences across SoCs
> + * @flags: Flags to represent IEP properties
> + */
> +struct icss_iep_plat_data {
> + struct regmap_config *config;
> + u32 reg_offs[ICSS_IEP_MAX_REGS];
> + u32 flags;
> +};
> +
> +struct icss_iep {
> + struct device *dev;
> + void __iomem *base;
> + const struct icss_iep_plat_data *plat_data;
> + struct regmap *map;
> + struct device_node *client_np;
> + unsigned long refclk_freq;
> + int clk_tick_time; /* one refclk tick time in ns */
> + struct ptp_clock_info ptp_info;
> + struct ptp_clock *ptp_clock;
> + struct mutex ptp_clk_mutex; /* PHC access serializer */
> + spinlock_t irq_lock; /* CMP IRQ vs icss_iep_ptp_enable access */
> + u32 def_inc;
> + s16 slow_cmp_inc;
> + u32 slow_cmp_count;
> + const struct icss_iep_clockops *ops;
> + void *clockops_data;
> + u32 cycle_time_ns;
> + u32 perout_enabled;
> + bool pps_enabled;
> + int cap_cmp_irq;
> + u64 period;
> + u32 latch_enable;
> +};
> +

Where is the comment you agreed to add on why we are using readl/writel
instead of regmap in certain areas?

> +/**
> + * icss_iep_get_count_hi() - Get the upper 32 bit IEP counter
> + * @iep: Pointer to structure representing IEP.
> + *
> + * Return: upper 32 bit IEP counter
> + */
> +int icss_iep_get_count_hi(struct icss_iep *iep)
> +{
> + u32 val = 0;
> +
> + if (iep && (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT))
> + val = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG1]);
> +
> + return val;
> +}
> +EXPORT_SYMBOL_GPL(icss_iep_get_count_hi);
> +
> +/**
> + * icss_iep_get_count_low() - Get the lower 32 bit IEP counter
> + * @iep: Pointer to structure representing IEP.
> + *
> + * Return: lower 32 bit IEP counter
> + */
> +int icss_iep_get_count_low(struct icss_iep *iep)
> +{
> + u32 val = 0;
> +
> + if (iep)
> + val = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG0]);
> +
> + return val;
> +}
> +EXPORT_SYMBOL_GPL(icss_iep_get_count_low);
> +
> +/**
> + * icss_iep_get_ptp_clock_idx() - Get PTP clock index using IEP driver
> + * @iep: Pointer to structure representing IEP.
> + *
> + * Return: PTP clock index, -1 if not registered
> + */
> +int icss_iep_get_ptp_clock_idx(struct icss_iep *iep)
> +{
> + if (!iep || !iep->ptp_clock)
> + return -1;
> + return ptp_clock_index(iep->ptp_clock);
> +}
> +EXPORT_SYMBOL_GPL(icss_iep_get_ptp_clock_idx);
> +
> +static void icss_iep_set_counter(struct icss_iep *iep, u64 ns)
> +{
> + if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
> + writel(upper_32_bits(ns), iep->base +
> + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG1]);
> + writel(upper_32_bits(ns), iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG0]);
> +}
> +
> +static void icss_iep_update_to_next_boundary(struct icss_iep *iep, u64 start_ns);
> +
> +static void icss_iep_settime(struct icss_iep *iep, u64 ns)
> +{
> + unsigned long flags;
> +
> + if (iep->ops && iep->ops->settime) {
> + iep->ops->settime(iep->clockops_data, ns);
> + return;
> + }
> +
> + spin_lock_irqsave(&iep->irq_lock, flags);
> + if (iep->pps_enabled || iep->perout_enabled)
> + writel(0, iep->base + iep->plat_data->reg_offs[ICSS_IEP_SYNC_CTRL_REG]);
> +
> + icss_iep_set_counter(iep, ns);
> +
> + if (iep->pps_enabled || iep->perout_enabled) {
> + icss_iep_update_to_next_boundary(iep, ns);
> + writel(IEP_SYNC_CTRL_SYNC_N_EN(0) | IEP_SYNC_CTRL_SYNC_EN,
> + iep->base + iep->plat_data->reg_offs[ICSS_IEP_SYNC_CTRL_REG]);
> + }
> + spin_unlock_irqrestore(&iep->irq_lock, flags);
> +}
> +
> +static u64 icss_iep_gettime(struct icss_iep *iep,
> + struct ptp_system_timestamp *sts)
> +{
> + u32 ts_hi = 0, ts_lo;
> + unsigned long flags;
> +
> + if (iep->ops && iep->ops->gettime)
> + return iep->ops->gettime(iep->clockops_data, sts);
> +
> + /* use local_irq_x() to make it work for both RT/non-RT */
> + local_irq_save(flags);
> +
> + /* no need to play with hi-lo, hi is latched when lo is read */
> + ptp_read_system_prets(sts);
> + ts_lo = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG0]);
> + ptp_read_system_postts(sts);
> + if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
> + ts_hi = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG1]);
> +
> + local_irq_restore(flags);
> +
> + return (u64)ts_lo | (u64)ts_hi << 32;
> +}
> +
> +static void icss_iep_enable(struct icss_iep *iep)
> +{
> + regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_CFG_REG,
> + IEP_GLOBAL_CFG_CNT_ENABLE,
> + IEP_GLOBAL_CFG_CNT_ENABLE);
> +}
> +
<snip>

--
cheers,
-roger