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 <rogerq@xxxxxx> >>> >>> 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 <rogerq@xxxxxx> >>> Signed-off-by: Lokesh Vutla <lokeshvutla@xxxxxx> >>> Signed-off-by: Murali Karicheri <m-karicheri2@xxxxxx> >>> Signed-off-by: Vignesh Raghavendra <vigneshr@xxxxxx> >>> Signed-off-by: MD Danish Anwar <danishanwar@xxxxxx> >>> --- >>> 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