Tegra194 device has multiple HTE instances also known as GTE (Generic hardware Timestamping Engine) which can timestamp subset of SoC lines/signals. This provider driver focuses on IRQ and GPIO lines and exposes timestamping ability on those lines to the consumers through HTE subsystem. Also, with this patch, added: - documentation about this provider and its capabilities at Documentation/hte. - Compilation support in Makefile and Kconfig Signed-off-by: Dipen Patel <dipenp@xxxxxxxxxx> --- Documentation/hte/index.rst | 21 ++ Documentation/hte/tegra194-hte.rst | 65 ++++ Documentation/index.rst | 1 + drivers/hte/Kconfig | 12 + drivers/hte/Makefile | 1 + drivers/hte/hte-tegra194.c | 554 +++++++++++++++++++++++++++++ 6 files changed, 654 insertions(+) create mode 100644 Documentation/hte/index.rst create mode 100644 Documentation/hte/tegra194-hte.rst create mode 100644 drivers/hte/hte-tegra194.c diff --git a/Documentation/hte/index.rst b/Documentation/hte/index.rst new file mode 100644 index 000000000000..f311ebec6b47 --- /dev/null +++ b/Documentation/hte/index.rst @@ -0,0 +1,21 @@ +.. SPDX-License-Identifier: GPL-2.0 + +============================================ +The Linux Hardware Timestamping Engine (HTE) +============================================ + +The HTE Subsystem +================= + +.. toctree:: + :maxdepth: 1 + + hte + +HTE Tegra Provider +================== + +.. toctree:: + :maxdepth: 1 + + tegra194-hte \ No newline at end of file diff --git a/Documentation/hte/tegra194-hte.rst b/Documentation/hte/tegra194-hte.rst new file mode 100644 index 000000000000..c23eaafcf080 --- /dev/null +++ b/Documentation/hte/tegra194-hte.rst @@ -0,0 +1,65 @@ +HTE Kernel provider driver +========================== + +Description +----------- +The Nvidia tegra194 chip has many hardware timestamping engine (HTE) instances +known as generic timestamping engine (GTE). This provider driver implements +two GTE instances 1) GPIO GTE and 2) IRQ GTE. The both GTEs instances get the +timestamp from the system counter TSC which has 31.25MHz clock rate, and the +driver converts clock tick rate to nano seconds before storing it as timestamp +value. + +GPIO GTE +-------- + +This GTE instance help timestamps GPIO in real time, for that to happen GPIO +needs to be configured as input and IRQ needs to ba enabled as well. The only +always on (AON) gpio controller instance supports timestamping GPIOs in +realtime and it has 39 GPIO lines. There is also a dependency on AON GPIO +controller as it requires very specific bits to be set in GPIO config register. +It in a way creates cyclic dependency between GTE and GPIO controller. The GTE +GPIO functionality is accessed from the GPIOLIB. It can support both the in +kernel and userspace consumers. In the later case, requests go through GPIOLIB +CDEV framework. The below APIs are added in GPIOLIB framework to access HTE +subsystem and GPIO GTE for in kernel consumers. + +.. c:function:: int gpiod_hw_timestamp_control( struct gpio_desc *desc, bool enable ) + + To enable HTE on given GPIO line. + +.. c:function:: u64 gpiod_get_hw_timestamp( struct gpio_desc *desc, bool block ) + + To retrieve hardwre timestamp in nano seconds. + +.. c:function:: bool gpiod_is_hw_timestamp_enabled( const struct gpio_desc *desc ) + + To query if HTE is enabled on the given GPIO. + +There is hte-tegra194-gpio-test.c, located in ``drivers/hte/`` directory, test +driver which demonstrates above APIs for the Jetson AGX platform. For userspace +consumers, GPIO_V2_LINE_FLAG_EVENT_CLOCK_HARDWARE flag must be specifed during +IOCTL calls, refer ``tools/gpio/gpio-event-mon.c``, which returns the timestamp +in nano second. + +IRQ GTE +-------- + +This GTE instance helps timestamp LIC IRQ lines in real time. There are 352 IRQ +lines which this instance can help timestamp realtime. The hte devicetree +binding described at ``Documentation/devicetree/bindings/hte/`` gives out +example how consumer can request IRQ line, since it is one to one mapping, +consumers can simply specify IRQ number that they are interested in. There is +no userspace consumer support for this GTE instance. The sample test code +hte-tegra194-irq-test.c, located in ``drivers/hte/`` directory, +demonstrates how to use IRQ GTE instance. The below is sample device tree +snippet code for the test driver:: + + tegra_hte_irq_test { + compatible = "nvidia,tegra194-hte-irq-test"; + htes = <&tegra_hte_lic 0x19>; + hte-names = "hte-lic"; + }; + +The source code of the driver both IRQ and GPIO GTE is locate at +``drivers/hte/hte-tegra194.c``. \ No newline at end of file diff --git a/Documentation/index.rst b/Documentation/index.rst index 1b13c2445e87..b41118577fe6 100644 --- a/Documentation/index.rst +++ b/Documentation/index.rst @@ -138,6 +138,7 @@ needed). misc-devices/index scheduler/index mhi/index + hte/index Architecture-agnostic documentation ----------------------------------- diff --git a/drivers/hte/Kconfig b/drivers/hte/Kconfig index 394e112f7dfb..f7b01fcc7190 100644 --- a/drivers/hte/Kconfig +++ b/drivers/hte/Kconfig @@ -20,3 +20,15 @@ menuconfig HTE If unsure, say no. +if HTE + +config HTE_TEGRA194 + tristate "NVIDIA Tegra194 HTE Support" + depends on ARCH_TEGRA_194_SOC + help + Enable this option for integrated hardware timestamping engine also + known as generic timestamping engine (GTE) support on NVIDIA Tegra194 + systems-on-chip. The driver supports 352 LIC IRQs and 39 AON GPIOs + lines for timestamping in realtime. + +endif diff --git a/drivers/hte/Makefile b/drivers/hte/Makefile index 9899dbe516f7..52f978cfc913 100644 --- a/drivers/hte/Makefile +++ b/drivers/hte/Makefile @@ -1 +1,2 @@ obj-$(CONFIG_HTE) += hte.o +obj-$(CONFIG_HTE_TEGRA194) += hte-tegra194.o \ No newline at end of file diff --git a/drivers/hte/hte-tegra194.c b/drivers/hte/hte-tegra194.c new file mode 100644 index 000000000000..8ad10efd3641 --- /dev/null +++ b/drivers/hte/hte-tegra194.c @@ -0,0 +1,554 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2021 NVIDIA Corporation + * + * Author: Dipen Patel <dipenp@xxxxxxxxxx> + */ + +#include <linux/err.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/stat.h> +#include <linux/interrupt.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/hte.h> +#include <linux/uaccess.h> + +#define HTE_SUSPEND 0 + +/* HTE source clock TSC is 31.25MHz */ +#define HTE_TS_CLK_RATE_HZ 31250000ULL +#define HTE_CLK_RATE_NS 32 +#define HTE_TS_NS_SHIFT __builtin_ctz(HTE_CLK_RATE_NS) + +#define NV_AON_SLICE_INVALID -1 + +/* AON HTE line map For slice 1 */ +#define NV_AON_HTE_SLICE1_IRQ_GPIO_28 12 +#define NV_AON_HTE_SLICE1_IRQ_GPIO_29 13 + +/* AON HTE line map For slice 2 */ +#define NV_AON_HTE_SLICE2_IRQ_GPIO_0 0 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_1 1 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_2 2 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_3 3 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_4 4 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_5 5 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_6 6 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_7 7 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_8 8 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_9 9 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_10 10 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_11 11 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_12 12 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_13 13 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_14 14 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_15 15 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_16 16 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_17 17 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_18 18 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_19 19 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_20 20 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_21 21 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_22 22 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_23 23 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_24 24 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_25 25 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_26 26 +#define NV_AON_HTE_SLICE2_IRQ_GPIO_27 27 + +/* AON GPIO port AA pins */ +#define NV_AON_GPIO_PORT_AA_0 0 +#define NV_AON_GPIO_PORT_AA_1 1 +#define NV_AON_GPIO_PORT_AA_2 2 +#define NV_AON_GPIO_PORT_AA_3 3 +#define NV_AON_GPIO_PORT_AA_4 4 +#define NV_AON_GPIO_PORT_AA_5 5 +#define NV_AON_GPIO_PORT_AA_6 6 +#define NV_AON_GPIO_PORT_AA_7 7 + +/* AON GPIO port BB pins */ +#define NV_AON_GPIO_PORT_BB_0 8 +#define NV_AON_GPIO_PORT_BB_1 9 +#define NV_AON_GPIO_PORT_BB_2 10 +#define NV_AON_GPIO_PORT_BB_3 11 + +/* AON GPIO port CC pins */ +#define NV_AON_GPIO_PORT_CC_0 16 +#define NV_AON_GPIO_PORT_CC_1 17 +#define NV_AON_GPIO_PORT_CC_2 18 +#define NV_AON_GPIO_PORT_CC_3 19 +#define NV_AON_GPIO_PORT_CC_4 20 +#define NV_AON_GPIO_PORT_CC_5 21 +#define NV_AON_GPIO_PORT_CC_6 22 +#define NV_AON_GPIO_PORT_CC_7 23 + +/* AON GPIO port DD pins */ +#define NV_AON_GPIO_PORT_DD_0 24 +#define NV_AON_GPIO_PORT_DD_1 25 +#define NV_AON_GPIO_PORT_DD_2 26 + +/* AON GPIO port EE pins */ +#define NV_AON_GPIO_PORT_EE_0 32 +#define NV_AON_GPIO_PORT_EE_1 33 +#define NV_AON_GPIO_PORT_EE_2 34 +#define NV_AON_GPIO_PORT_EE_3 35 +#define NV_AON_GPIO_PORT_EE_4 36 +#define NV_AON_GPIO_PORT_EE_5 37 +#define NV_AON_GPIO_PORT_EE_6 38 + + +#define HTE_TECTRL 0x0 +#define HTE_TETSCH 0x4 +#define HTE_TETSCL 0x8 +#define HTE_TESRC 0xC +#define HTE_TECCV 0x10 +#define HTE_TEPCV 0x14 +#define HTE_TECMD 0x1C +#define HTE_TESTATUS 0x20 +#define HTE_SLICE0_TETEN 0x40 +#define HTE_SLICE1_TETEN 0x60 + +#define HTE_SLICE_SIZE (HTE_SLICE1_TETEN - HTE_SLICE0_TETEN) + +#define HTE_TECTRL_ENABLE_ENABLE 0x1 + +#define HTE_TECTRL_OCCU_SHIFT 0x8 +#define HTE_TECTRL_INTR_SHIFT 0x1 +#define HTE_TECTRL_INTR_ENABLE 0x1 + +#define HTE_TESRC_SLICE_SHIFT 16 +#define HTE_TESRC_SLICE_DEFAULT_MASK 0xFF + +#define HTE_TECMD_CMD_POP 0x1 + +#define HTE_TESTATUS_OCCUPANCY_SHIFT 8 +#define HTE_TESTATUS_OCCUPANCY_MASK 0xFF + +struct hte_slices { + u32 r_val; + unsigned long flags; + /* to prevent lines mapped to same slice updating its register */ + spinlock_t s_lock; +}; + +struct tegra_hte_line_mapped { + int slice; + u32 bit_index; +}; + +struct tegra_hte_line_table { + int map_sz; + const struct tegra_hte_line_mapped *map; +}; + +struct tegra_hte_soc { + int hte_irq; + u32 itr_thrshld; + u32 conf_rval; + struct hte_slices *sl; + const struct tegra_hte_line_table *line_map; + struct hte_chip *chip; + void __iomem *regs; +}; + +static const struct tegra_hte_line_mapped tegra194_aon_gpio_map[] = { + /* gpio, slice, bit_index */ + [NV_AON_GPIO_PORT_AA_0] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_11}, + [NV_AON_GPIO_PORT_AA_1] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_10}, + [NV_AON_GPIO_PORT_AA_2] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_9}, + [NV_AON_GPIO_PORT_AA_3] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_8}, + [NV_AON_GPIO_PORT_AA_4] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_7}, + [NV_AON_GPIO_PORT_AA_5] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_6}, + [NV_AON_GPIO_PORT_AA_6] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_5}, + [NV_AON_GPIO_PORT_AA_7] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_4}, + [NV_AON_GPIO_PORT_BB_0] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_3}, + [NV_AON_GPIO_PORT_BB_1] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_2}, + [NV_AON_GPIO_PORT_BB_2] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_1}, + [NV_AON_GPIO_PORT_BB_3] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_0}, + [12] = {NV_AON_SLICE_INVALID, 0}, + [13] = {NV_AON_SLICE_INVALID, 0}, + [14] = {NV_AON_SLICE_INVALID, 0}, + [15] = {NV_AON_SLICE_INVALID, 0}, + [NV_AON_GPIO_PORT_CC_0] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_22}, + [NV_AON_GPIO_PORT_CC_1] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_21}, + [NV_AON_GPIO_PORT_CC_2] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_20}, + [NV_AON_GPIO_PORT_CC_3] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_19}, + [NV_AON_GPIO_PORT_CC_4] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_18}, + [NV_AON_GPIO_PORT_CC_5] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_17}, + [NV_AON_GPIO_PORT_CC_6] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_16}, + [NV_AON_GPIO_PORT_CC_7] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_15}, + [NV_AON_GPIO_PORT_DD_0] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_14}, + [NV_AON_GPIO_PORT_DD_1] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_13}, + [NV_AON_GPIO_PORT_DD_2] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_12}, + [27] = {NV_AON_SLICE_INVALID, 0}, + [28] = {NV_AON_SLICE_INVALID, 0}, + [29] = {NV_AON_SLICE_INVALID, 0}, + [30] = {NV_AON_SLICE_INVALID, 0}, + [31] = {NV_AON_SLICE_INVALID, 0}, + [NV_AON_GPIO_PORT_EE_0] = {1, NV_AON_HTE_SLICE1_IRQ_GPIO_29}, + [NV_AON_GPIO_PORT_EE_1] = {1, NV_AON_HTE_SLICE1_IRQ_GPIO_28}, + [NV_AON_GPIO_PORT_EE_2] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_27}, + [NV_AON_GPIO_PORT_EE_3] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_26}, + [NV_AON_GPIO_PORT_EE_4] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_25}, + [NV_AON_GPIO_PORT_EE_5] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_24}, + [NV_AON_GPIO_PORT_EE_6] = {2, NV_AON_HTE_SLICE2_IRQ_GPIO_23}, +}; + +static const struct tegra_hte_line_table aon_hte_map = { + .map_sz = ARRAY_SIZE(tegra194_aon_gpio_map), + .map = tegra194_aon_gpio_map, +}; + +static inline u32 tegra_hte_readl(struct tegra_hte_soc *hte, u32 reg) +{ + return readl(hte->regs + reg); +} + +static inline void tegra_hte_writel(struct tegra_hte_soc *hte, u32 reg, + u32 val) +{ + writel(val, hte->regs + reg); +} + +static inline int tegra_hte_map_to_line_id(u32 eid, struct tegra_hte_soc *gs, + u32 *mapped) +{ + const struct tegra_hte_line_mapped *m; + + if (gs->line_map) { + m = gs->line_map->map; + if (eid > gs->line_map->map_sz) + return -EINVAL; + if (m[eid].slice == NV_AON_SLICE_INVALID) + return -EINVAL; + + *mapped = (m[eid].slice << 5) + m[eid].bit_index; + } else { + *mapped = eid; + } + + return 0; +} + +static int tegra_hte_line_xlate(struct hte_chip *gc, + const struct of_phandle_args *args, + struct hte_ts_desc *desc, u32 *xlated_id) +{ + int ret = 0; + + if (!gc || !desc || !xlated_id) + return -EINVAL; + + if (args) { + if (gc->of_hte_n_cells < 1) + return -EINVAL; + + if (args->args_count != gc->of_hte_n_cells) + return -EINVAL; + + desc->con_id = args->args[0]; + } + + ret = tegra_hte_map_to_line_id(desc->con_id, gc->data, + xlated_id); + if (ret < 0) { + dev_dbg(gc->dev, "con_id:%u mapping failed\n", + desc->con_id); + return ret; + } + + if (*xlated_id > gc->nlines) + return -EINVAL; + + dev_dbg(gc->dev, "requested id:%u, xlated id:%u\n", + desc->con_id, *xlated_id); + + return 0; +} + +static int tegra_hte_en_dis_common(struct hte_chip *chip, u32 line_id, bool en) +{ + u32 slice, sl_bit_shift, line_bit, val, reg; + struct tegra_hte_soc *gs; + + sl_bit_shift = __builtin_ctz(HTE_SLICE_SIZE); + + if (!chip) + return -EINVAL; + + gs = (struct tegra_hte_soc *)chip->data; + + if (line_id > chip->nlines) { + dev_err(chip->dev, + "line id: %u is not supported by this controller\n", + line_id); + return -EINVAL; + } + + slice = line_id >> sl_bit_shift; + line_bit = line_id & (HTE_SLICE_SIZE - 1); + reg = (slice << sl_bit_shift) + HTE_SLICE0_TETEN; + + spin_lock(&gs->sl[slice].s_lock); + + if (test_bit(HTE_SUSPEND, &gs->sl[slice].flags)) { + spin_unlock(&gs->sl[slice].s_lock); + dev_dbg(chip->dev, "device suspended"); + return -EBUSY; + } + + val = tegra_hte_readl(gs, reg); + if (en) + val = val | (1 << line_bit); + else + val = val & (~(1 << line_bit)); + tegra_hte_writel(gs, reg, val); + + spin_unlock(&gs->sl[slice].s_lock); + + dev_dbg(chip->dev, "line: %u, slice %u, line_bit %u, reg:0x%x\n", + line_id, slice, line_bit, reg); + + return 0; +} + +static int tegra_hte_request(struct hte_chip *chip, u32 line_id) +{ + return tegra_hte_en_dis_common(chip, line_id, true); +} + +static int tegra_hte_release(struct hte_chip *chip, u32 line_id) +{ + return tegra_hte_en_dis_common(chip, line_id, false); +} + +static int tegra_hte_clk_src_info(struct hte_chip *chip, + struct hte_clk_info *ci) +{ + (void)chip; + + ci->hz = HTE_TS_CLK_RATE_HZ; + ci->type = CLOCK_MONOTONIC; + + return 0; +} + +static void tegra_hte_read_fifo(struct tegra_hte_soc *gs) +{ + u32 tsh, tsl, src, pv, cv, acv, slice, bit_index, line_id; + u64 tsc; + int dir; + struct hte_ts_data el; + + while ((tegra_hte_readl(gs, HTE_TESTATUS) >> + HTE_TESTATUS_OCCUPANCY_SHIFT) & + HTE_TESTATUS_OCCUPANCY_MASK) { + tsh = tegra_hte_readl(gs, HTE_TETSCH); + tsl = tegra_hte_readl(gs, HTE_TETSCL); + tsc = (((u64)tsh << 32) | tsl); + + src = tegra_hte_readl(gs, HTE_TESRC); + slice = (src >> HTE_TESRC_SLICE_SHIFT) & + HTE_TESRC_SLICE_DEFAULT_MASK; + + pv = tegra_hte_readl(gs, HTE_TEPCV); + cv = tegra_hte_readl(gs, HTE_TECCV); + acv = pv ^ cv; + while (acv) { + bit_index = __builtin_ctz(acv); + if ((pv >> bit_index) & BIT(0)) + dir = HTE_EVENT_RISING_EDGE; + else + dir = HTE_EVENT_FALLING_EDGE; + + line_id = bit_index + (slice << 5); + el.dir = dir; + el.tsc = tsc << HTE_TS_NS_SHIFT; + hte_push_ts_ns_atomic(gs->chip, line_id, &el, + sizeof(el)); + acv &= ~BIT(bit_index); + } + tegra_hte_writel(gs, HTE_TECMD, HTE_TECMD_CMD_POP); + } +} + +static irqreturn_t tegra_hte_isr(int irq, void *dev_id) +{ + struct tegra_hte_soc *gs = dev_id; + + tegra_hte_read_fifo(gs); + + return IRQ_HANDLED; +} + +static const struct of_device_id tegra_hte_of_match[] = { + { .compatible = "nvidia,tegra194-gte-lic"}, + { .compatible = "nvidia,tegra194-gte-aon", .data = &aon_hte_map}, + { } +}; +MODULE_DEVICE_TABLE(of, tegra_hte_of_match); + +static const struct hte_ops g_ops = { + .request = tegra_hte_request, + .release = tegra_hte_release, + .enable = tegra_hte_request, + .disable = tegra_hte_release, + .get_clk_src_info = tegra_hte_clk_src_info, +}; + +static int tegra_hte_probe(struct platform_device *pdev) +{ + int ret; + u32 i, slices, val = 0; + struct device *dev; + struct tegra_hte_soc *hte_dev; + struct hte_chip *gc; + + dev = &pdev->dev; + + hte_dev = devm_kzalloc(dev, sizeof(*hte_dev), GFP_KERNEL); + if (!hte_dev) + return -ENOMEM; + + gc = devm_kzalloc(dev, sizeof(*gc), GFP_KERNEL); + if (!gc) + return -ENOMEM; + + dev_set_drvdata(&pdev->dev, hte_dev); + hte_dev->line_map = of_device_get_match_data(&pdev->dev); + + hte_dev->regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(hte_dev->regs)) + return PTR_ERR(hte_dev->regs); + + ret = of_property_read_u32(dev->of_node, "int-threshold", + &hte_dev->itr_thrshld); + if (ret != 0) + hte_dev->itr_thrshld = 1; + + ret = of_property_read_u32(dev->of_node, "slices", &slices); + if (ret != 0) { + dev_err(dev, "Could not read slices\n"); + return -EINVAL; + } + + hte_dev->sl = devm_kzalloc(dev, sizeof(struct hte_slices) * slices, + GFP_KERNEL); + if (!hte_dev->sl) + return -ENOMEM; + + ret = platform_get_irq(pdev, 0); + if (ret < 0) { + dev_err(dev, "get irq failed.\n"); + return ret; + } + hte_dev->hte_irq = ret; + ret = devm_request_irq(dev, hte_dev->hte_irq, tegra_hte_isr, 0, + dev_name(dev), hte_dev); + if (ret < 0) { + dev_err(dev, "request irq failed.\n"); + return ret; + } + + gc->nlines = slices << 5; + gc->ops = &g_ops; + gc->dev = dev; + hte_dev->chip = gc; + gc->data = (void *)hte_dev; + gc->xlate = tegra_hte_line_xlate; + gc->of_hte_n_cells = 1; + + ret = hte_register_chip(hte_dev->chip); + + if (ret) + dev_err(gc->dev, "hte chip register failed"); + + for (i = 0; i < slices; i++) { + hte_dev->sl[i].flags = 0; + spin_lock_init(&hte_dev->sl[i].s_lock); + } + + val = HTE_TECTRL_ENABLE_ENABLE | + (HTE_TECTRL_INTR_ENABLE << HTE_TECTRL_INTR_SHIFT) | + (hte_dev->itr_thrshld << HTE_TECTRL_OCCU_SHIFT); + tegra_hte_writel(hte_dev, HTE_TECTRL, val); + + dev_dbg(gc->dev, "lines: %d, slices:%d", gc->nlines, slices); + return 0; +} + +static int tegra_hte_remove(struct platform_device *pdev) +{ + struct tegra_hte_soc *gs = dev_get_drvdata(&pdev->dev); + + tegra_hte_writel(gs, HTE_TECTRL, 0); + + return hte_unregister_chip(gs->chip); +} + +#ifdef CONFIG_PM_SLEEP +static int tegra_hte_resume_early(struct device *dev) +{ + u32 i; + struct tegra_hte_soc *gs = dev_get_drvdata(dev); + u32 slices = gs->chip->nlines >> 5; + u32 sl_bit_shift = __builtin_ctz(HTE_SLICE_SIZE); + + tegra_hte_writel(gs, HTE_TECTRL, gs->conf_rval); + + for (i = 0; i < slices; i++) { + spin_lock(&gs->sl[i].s_lock); + tegra_hte_writel(gs, + ((i << sl_bit_shift) + HTE_SLICE0_TETEN), + gs->sl[i].r_val); + clear_bit(HTE_SUSPEND, &gs->sl[i].flags); + spin_unlock(&gs->sl[i].s_lock); + } + + return 0; +} + +static int tegra_hte_suspend_late(struct device *dev) +{ + u32 i; + struct tegra_hte_soc *gs = dev_get_drvdata(dev); + u32 slices = gs->chip->nlines >> 5; + u32 sl_bit_shift = __builtin_ctz(HTE_SLICE_SIZE); + + gs->conf_rval = tegra_hte_readl(gs, HTE_TECTRL); + for (i = 0; i < slices; i++) { + spin_lock(&gs->sl[i].s_lock); + gs->sl[i].r_val = tegra_hte_readl(gs, + ((i << sl_bit_shift) + HTE_SLICE0_TETEN)); + set_bit(HTE_SUSPEND, &gs->sl[i].flags); + spin_unlock(&gs->sl[i].s_lock); + } + + return 0; +} +#endif + +static const struct dev_pm_ops tegra_hte_pm = { + SET_LATE_SYSTEM_SLEEP_PM_OPS(tegra_hte_suspend_late, + tegra_hte_resume_early) +}; + +static struct platform_driver tegra_hte_driver = { + .probe = tegra_hte_probe, + .remove = tegra_hte_remove, + .driver = { + .name = "tegra_hte", + .pm = &tegra_hte_pm, + .of_match_table = tegra_hte_of_match, + }, +}; + +module_platform_driver(tegra_hte_driver); + +MODULE_AUTHOR("Dipen Patel <dipenp@xxxxxxxxxx>"); +MODULE_DESCRIPTION("NVIDIA Tegra HTE (Hardware Timestamping Engine) driver"); +MODULE_LICENSE("GPL v2"); -- 2.17.1