Add support for Qualcomm I2C QUP driver which is inspired from corresponding driver in Linux: drivers/i2c/busses/i2c-qup.c.
Currently this driver only support FIFO polling mode which is sufficient to support devices like eeprom, rtc etc.
Co-developed-by: Mike Worsfold mworsfold@impinj.com Signed-off-by: Mike Worsfold mworsfold@impinj.com Signed-off-by: Sumit Garg sumit.garg@linaro.org --- drivers/i2c/Kconfig | 6 + drivers/i2c/Makefile | 1 + drivers/i2c/qup_i2c.c | 592 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 599 insertions(+) create mode 100644 drivers/i2c/qup_i2c.c
diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig index 76e19918aa..2a1d36f91a 100644 --- a/drivers/i2c/Kconfig +++ b/drivers/i2c/Kconfig @@ -635,6 +635,12 @@ config SYS_I2C_TEGRA help Support for NVIDIA I2C controller available in Tegra SoCs.
+config SYS_I2C_QUP + bool "Qualcomm I2C controller" + depends on ARCH_SNAPDRAGON + help + Support for Qualcomm I2C controller. + config SYS_I2C_UNIPHIER bool "UniPhier I2C driver" depends on ARCH_UNIPHIER && DM_I2C diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile index 920aafb91c..f6aa39dd7a 100644 --- a/drivers/i2c/Makefile +++ b/drivers/i2c/Makefile @@ -50,6 +50,7 @@ obj-$(CONFIG_SYS_I2C_SUN6I_P2WI) += sun6i_p2wi.o obj-$(CONFIG_SYS_I2C_SUN8I_RSB) += sun8i_rsb.o obj-$(CONFIG_SYS_I2C_SYNQUACER) += synquacer_i2c.o obj-$(CONFIG_SYS_I2C_TEGRA) += tegra_i2c.o +obj-$(CONFIG_SYS_I2C_QUP) += qup_i2c.o obj-$(CONFIG_SYS_I2C_UNIPHIER) += i2c-uniphier.o obj-$(CONFIG_SYS_I2C_UNIPHIER_F) += i2c-uniphier-f.o obj-$(CONFIG_SYS_I2C_VERSATILE) += i2c-versatile.o diff --git a/drivers/i2c/qup_i2c.c b/drivers/i2c/qup_i2c.c new file mode 100644 index 0000000000..6787fc75fc --- /dev/null +++ b/drivers/i2c/qup_i2c.c @@ -0,0 +1,592 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2009-2013, 2016-2018, The Linux Foundation. All rights reserved. + * Copyright (c) 2014, Sony Mobile Communications AB. + * Copyright (c) 2022-2023, Sumit Garg sumit.garg@linaro.org + * + * Inspired by corresponding driver in Linux: drivers/i2c/busses/i2c-qup.c + */ + +#include <init.h> +#include <env.h> +#include <common.h> +#include <log.h> +#include <dm/device_compat.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/compat.h> +#include <linux/bitops.h> +#include <asm/io.h> +#include <i2c.h> +#include <watchdog.h> +#include <fdtdec.h> +#include <clk.h> +#include <reset.h> +#include <asm/arch/gpio.h> +#include <cpu_func.h> +#include <asm/system.h> +#include <asm/gpio.h> +#include <dm.h> +#include <dm/pinctrl.h> + +/* QUP Registers */ +#define QUP_CONFIG 0x000 +#define QUP_STATE 0x004 +#define QUP_IO_MODE 0x008 +#define QUP_SW_RESET 0x00c +#define QUP_OPERATIONAL 0x018 +#define QUP_ERROR_FLAGS 0x01c +#define QUP_ERROR_FLAGS_EN 0x020 +#define QUP_TEST_CTRL 0x024 /* NOT USED */ +#define QUP_OPERATIONAL_MASK 0x028 +#define QUP_HW_VERSION 0x030 +#define QUP_MX_OUTPUT_CNT 0x100 +#define QUP_OUT_DEBUG 0x108 /* NOT USED */ +#define QUP_OUT_FIFO_CNT 0x10C /* NOT USED */ +#define QUP_OUT_FIFO_BASE 0x110 +#define QUP_MX_WRITE_CNT 0x150 +#define QUP_MX_INPUT_CNT 0x200 +#define QUP_MX_READ_CNT 0x208 +#define QUP_IN_READ_CUR 0x20C /* NOT USED */ +#define QUP_IN_DEBUG 0x210 /* NOT USED */ +#define QUP_IN_FIFO_CNT 0x214 /* NOT USED */ +#define QUP_IN_FIFO_BASE 0x218 +#define QUP_I2C_CLK_CTL 0x400 +#define QUP_I2C_STATUS 0x404 +#define QUP_I2C_MASTER_GEN 0x408 +#define QUP_I2C_MASTER_BUS_CLR 0x40C /* NOT USED */ + +/* QUP States and reset values */ +#define QUP_RESET_STATE 0 +#define QUP_RUN_STATE 1 +#define QUP_PAUSE_STATE 3 +#define QUP_STATE_MASK 3 + +#define QUP_STATE_VALID BIT(2) +#define QUP_I2C_MAST_GEN BIT(4) +#define QUP_I2C_FLUSH BIT(6) + +#define QUP_OPERATIONAL_RESET 0x000ff0 +#define QUP_I2C_STATUS_RESET 0xfffffc + +/* QUP OPERATIONAL FLAGS */ +#define QUP_I2C_NACK_FLAG BIT(3) +#define QUP_OUT_NOT_EMPTY BIT(4) +#define QUP_IN_NOT_EMPTY BIT(5) +#define QUP_OUT_FULL BIT(6) +#define QUP_OUT_SVC_FLAG BIT(8) +#define QUP_IN_SVC_FLAG BIT(9) +#define QUP_MX_OUTPUT_DONE BIT(10) +#define QUP_MX_INPUT_DONE BIT(11) +#define OUT_BLOCK_WRITE_REQ BIT(12) +#define IN_BLOCK_READ_REQ BIT(13) + +/* I2C mini core related values */ +#define QUP_NO_OUTPUT BIT(6) +#define QUP_NO_INPUT BIT(7) +#define QUP_CLOCK_AUTO_GATE BIT(13) +#define I2C_MINI_CORE (2 << 8) +#define I2C_N_VAL 15 +#define I2C_N_VAL_V2 7 + +/* Most significant word offset in FIFO port */ +#define QUP_MSW_SHIFT (I2C_N_VAL + 1) + +/* Packing/Unpacking words in FIFOs, and IO modes */ +#define QUP_OUTPUT_BLK_MODE BIT(10) +#define QUP_OUTPUT_BAM_MODE (BIT(10) | BIT(11)) +#define QUP_INPUT_BLK_MODE BIT(12) +#define QUP_INPUT_BAM_MODE (BIT(12) | BIT(13)) +#define QUP_BAM_MODE (QUP_OUTPUT_BAM_MODE | QUP_INPUT_BAM_MODE) +#define QUP_BLK_MODE (QUP_OUTPUT_BLK_MODE | QUP_INPUT_BLK_MODE) +#define QUP_UNPACK_EN BIT(14) +#define QUP_PACK_EN BIT(15) + +#define QUP_REPACK_EN (QUP_UNPACK_EN | QUP_PACK_EN) +#define QUP_V2_TAGS_EN 1 + +#define QUP_OUTPUT_BLOCK_SIZE(x) (((x) >> 0) & 0x03) +#define QUP_OUTPUT_FIFO_SIZE(x) (((x) >> 2) & 0x07) +#define QUP_INPUT_BLOCK_SIZE(x) (((x) >> 5) & 0x03) +#define QUP_INPUT_FIFO_SIZE(x) (((x) >> 7) & 0x07) + +/* QUP v2 tags */ +#define QUP_TAG_V2_START 0x81 +#define QUP_TAG_V2_DATAWR 0x82 +#define QUP_TAG_V2_DATAWR_STOP 0x83 +#define QUP_TAG_V2_DATARD 0x85 +#define QUP_TAG_V2_DATARD_NACK 0x86 +#define QUP_TAG_V2_DATARD_STOP 0x87 + +/* Status, Error flags */ +#define I2C_STATUS_WR_BUFFER_FULL BIT(0) +#define I2C_STATUS_BUS_ERROR BIT(2) +#define I2C_STATUS_PACKET_NACKED BIT(3) +#define I2C_STATUS_ARB_LOST BIT(4) +#define I2C_STATUS_INVALID_WRITE BIT(5) +#define I2C_STATUS_FAILED BIT(6) +#define I2C_STATUS_BUS_ACTIVE BIT(8) +#define I2C_STATUS_BUS_MASTER BIT(9) +#define I2C_STATUS_INVALID_TAG BIT(23) +#define I2C_STATUS_INVALID_READ_ADDR BIT(24) +#define I2C_STATUS_INVALID_READ_SEQ BIT(25) +#define I2C_STATUS_I2C_SDA BIT(26) +#define I2C_STATUS_I2C_SCL BIT(27) +#define I2C_STATUS_ERROR_MASK 0x38000fc +#define QUP_STATUS_ERROR_FLAGS 0x7c + +#define QUP_I2C_MX_CONFIG_DURING_RUN BIT(31) + +/* Minimum transfer timeout for i2c transfers in micro seconds */ +#define TOUT_CNT 2 * 1000 * 1000 + +/* Default values. Use these if FW query fails */ +#define DEFAULT_CLK_FREQ I2C_SPEED_STANDARD_RATE +#define DEFAULT_SRC_CLK 19200000 + +/* + * Max tags length (start, stop and maximum 2 bytes address) for each QUP + * data transfer + */ +#define QUP_MAX_TAGS_LEN 4 +/* Max data length for each DATARD tags */ +#define RECV_MAX_DATA_LEN 254 +/* TAG length for DATA READ in RX FIFO */ +#define READ_RX_TAGS_LEN 2 + +struct qup_i2c_priv { + phys_addr_t base; + struct clk core; + struct clk iface; + u32 in_fifo_sz; + u32 out_fifo_sz; + u32 clk_ctl; + u32 config_run; +}; + +static inline u8 i2c_8bit_addr_from_msg(const struct i2c_msg *msg) +{ + return (msg->addr << 1) | (msg->flags & I2C_M_RD ? 1 : 0); +} + +static int qup_i2c_poll_state_mask(struct qup_i2c_priv *qup, + u32 req_state, u32 req_mask) +{ + int retries = 1; + u32 state; + + /* + * State transition takes 3 AHB clocks cycles + 3 I2C master clock + * cycles. So retry once after a 1uS delay. + */ + do { + state = readl(qup->base + QUP_STATE); + + if (state & QUP_STATE_VALID && + (state & req_mask) == req_state) + return 0; + + udelay(1); + } while (retries--); + + return -ETIMEDOUT; +} + +static int qup_i2c_poll_state(struct qup_i2c_priv *qup, u32 req_state) +{ + return qup_i2c_poll_state_mask(qup, req_state, QUP_STATE_MASK); +} + +static int qup_i2c_poll_state_valid(struct qup_i2c_priv *qup) +{ + return qup_i2c_poll_state_mask(qup, 0, 0); +} + +static int qup_i2c_poll_state_i2c_master(struct qup_i2c_priv *qup) +{ + return qup_i2c_poll_state_mask(qup, QUP_I2C_MAST_GEN, QUP_I2C_MAST_GEN); +} + +static int qup_i2c_change_state(struct qup_i2c_priv *qup, u32 state) +{ + if (qup_i2c_poll_state_valid(qup) != 0) + return -EIO; + + writel(state, qup->base + QUP_STATE); + + if (qup_i2c_poll_state(qup, state) != 0) + return -EIO; + return 0; +} + +/* + * Function to check wheather Input or Output FIFO + * has data to be serviced + */ +static int qup_i2c_check_fifo_status(struct qup_i2c_priv *qup, u32 reg_addr, + u32 flags) +{ + unsigned long count = TOUT_CNT; + u32 val, status_flag; + int ret = 0; + + do { + val = readl(qup->base + reg_addr); + status_flag = val & flags; + + if (!count) { + printf("%s, timeout\n", __func__); + ret = -ETIMEDOUT; + break; + } + + count--; + udelay(1); + } while (!status_flag); + + return ret; +} + +/* + * Function to configure Input and Output enable/disable + */ +static void qup_i2c_enable_io_config(struct qup_i2c_priv *qup, u32 write_cnt, + u32 read_cnt) +{ + u32 qup_config = I2C_MINI_CORE | I2C_N_VAL_V2; + + writel(qup->config_run | write_cnt, qup->base + QUP_MX_WRITE_CNT); + + if (read_cnt) + writel(qup->config_run | read_cnt, qup->base + QUP_MX_READ_CNT); + else + qup_config |= QUP_NO_INPUT; + + writel(qup_config, qup->base + QUP_CONFIG); +} + +static unsigned int qup_i2c_read_word(struct qup_i2c_priv *qup) +{ + return readl(qup->base + QUP_IN_FIFO_BASE); +} + +static void qup_i2c_write_word(struct qup_i2c_priv *qup, u32 word) +{ + writel(word, qup->base + QUP_OUT_FIFO_BASE); +} + +static int qup_i2c_blsp_read(struct qup_i2c_priv *qup, unsigned int addr, + bool last, u8 *buffer, unsigned int bytes) +{ + unsigned int i, j, word; + int ret = 0; + + /* FIFO mode size limitation, for larger size implement block mode */ + if (bytes > (qup->in_fifo_sz - READ_RX_TAGS_LEN)) + return -EINVAL; + + qup_i2c_enable_io_config(qup, QUP_MAX_TAGS_LEN, + bytes + READ_RX_TAGS_LEN); + + if (last) + qup_i2c_write_word(qup, QUP_TAG_V2_START | addr << 8 | + QUP_TAG_V2_DATARD_STOP << 16 | + bytes << 24); + else + qup_i2c_write_word(qup, QUP_TAG_V2_START | addr << 8 | + QUP_TAG_V2_DATARD << 16 | bytes << 24); + + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); + if (ret) + return ret; + + ret = qup_i2c_check_fifo_status(qup, QUP_OPERATIONAL, QUP_OUT_SVC_FLAG); + if (ret) + return ret; + writel(QUP_OUT_SVC_FLAG, qup->base + QUP_OPERATIONAL); + + ret = qup_i2c_check_fifo_status(qup, QUP_OPERATIONAL, QUP_IN_SVC_FLAG); + if (ret) + return ret; + writel(QUP_IN_SVC_FLAG, qup->base + QUP_OPERATIONAL); + + word = qup_i2c_read_word(qup); + *(buffer++) = (word >> (8 * READ_RX_TAGS_LEN)) & 0xff; + if (bytes > 1) + *(buffer++) = (word >> (8 * (READ_RX_TAGS_LEN + 1))) & 0xff; + + for (i = 2; i < bytes; i += 4) { + word = qup_i2c_read_word(qup); + + for (j = 0; j < 4; j++) { + if ((i + j) == bytes) + break; + *buffer = (word >> (j * 8)) & 0xff; + buffer++; + } + } + + ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE); + return ret; +} + +static int qup_i2c_blsp_write(struct qup_i2c_priv *qup, unsigned int addr, + bool first, bool last, const u8 *buffer, + unsigned int bytes) +{ + unsigned int i; + u32 word = 0; + int ret = 0; + + /* FIFO mode size limitation, for larger size implement block mode */ + if (bytes > (qup->out_fifo_sz - QUP_MAX_TAGS_LEN)) + return -EINVAL; + + qup_i2c_enable_io_config(qup, bytes + QUP_MAX_TAGS_LEN, 0); + + if (first) { + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); + if (ret) + return ret; + + writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL); + + ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE); + if (ret) + return ret; + } + + if (last) + qup_i2c_write_word(qup, QUP_TAG_V2_START | addr << 8 | + QUP_TAG_V2_DATAWR_STOP << 16 | + bytes << 24); + else + qup_i2c_write_word(qup, QUP_TAG_V2_START | addr << 8 | + QUP_TAG_V2_DATAWR << 16 | bytes << 24); + + for (i = 0; i < bytes; i++) { + /* Write the byte of data */ + word |= *buffer << ((i % 4) * 8); + if ((i % 4) == 3) { + qup_i2c_write_word(qup, word); + word = 0; + } + buffer++; + } + + if ((i % 4) != 0) + qup_i2c_write_word(qup, word); + + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); + if (ret) + return ret; + + ret = qup_i2c_check_fifo_status(qup, QUP_OPERATIONAL, QUP_OUT_SVC_FLAG); + if (ret) + return ret; + writel(QUP_OUT_SVC_FLAG, qup->base + QUP_OPERATIONAL); + + ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE); + return ret; +} + +static void qup_i2c_conf_mode_v2(struct qup_i2c_priv *qup) +{ + u32 io_mode = QUP_REPACK_EN; + + writel(0, qup->base + QUP_MX_OUTPUT_CNT); + writel(0, qup->base + QUP_MX_INPUT_CNT); + + writel(io_mode, qup->base + QUP_IO_MODE); +} + +static int qup_i2c_xfer_v2(struct udevice *bus, struct i2c_msg msgs[], int num) +{ + struct qup_i2c_priv *qup = dev_get_priv(bus); + int ret, idx = 0; + u32 i2c_addr; + + writel(1, qup->base + QUP_SW_RESET); + ret = qup_i2c_poll_state(qup, QUP_RESET_STATE); + if (ret) + goto out; + + /* Configure QUP as I2C mini core */ + writel(I2C_MINI_CORE | I2C_N_VAL_V2 | QUP_NO_INPUT, + qup->base + QUP_CONFIG); + writel(QUP_V2_TAGS_EN, qup->base + QUP_I2C_MASTER_GEN); + + if (qup_i2c_poll_state_i2c_master(qup)) { + ret = -EIO; + goto out; + } + + qup_i2c_conf_mode_v2(qup); + + for (idx = 0; idx < num; idx++) { + struct i2c_msg *m = &msgs[idx]; + + qup->config_run = !idx ? 0 : QUP_I2C_MX_CONFIG_DURING_RUN; + i2c_addr = i2c_8bit_addr_from_msg(m); + + if (m->flags & I2C_M_RD) + ret = qup_i2c_blsp_read(qup, i2c_addr, idx == (num - 1), + m->buf, m->len); + else + ret = qup_i2c_blsp_write(qup, i2c_addr, idx == 0, + idx == (num - 1), m->buf, + m->len); + if (ret) + break; + } +out: + qup_i2c_change_state(qup, QUP_RESET_STATE); + return ret; +} + +static int qup_i2c_enable_clocks(struct udevice *dev, struct qup_i2c_priv *qup) +{ + int ret; + + ret = clk_enable(&qup->core); + if (ret) { + dev_err(dev, "clk_enable failed %d\n", ret); + return ret; + } + + ret = clk_enable(&qup->iface); + if (ret) { + dev_err(dev, "clk_enable failed %d\n", ret); + return ret; + } + + return 0; +} + +static int qup_i2c_probe(struct udevice *dev) +{ + static const int blk_sizes[] = {4, 16, 32}; + struct qup_i2c_priv *qup = dev_get_priv(dev); + u32 io_mode, hw_ver, size, size_idx; + int ret; + + qup->base = (phys_addr_t)dev_read_addr_ptr(dev); + if (!qup->base) + return -EINVAL; + + ret = clk_get_by_name(dev, "core", &qup->core); + if (ret) { + pr_err("clk_get_by_name(core) failed: %d\n", ret); + return ret; + } + ret = clk_get_by_name(dev, "iface", &qup->iface); + if (ret) { + pr_err("clk_get_by_name(iface) failed: %d\n", ret); + return ret; + } + qup_i2c_enable_clocks(dev, qup); + + writel(1, qup->base + QUP_SW_RESET); + ret = qup_i2c_poll_state_valid(qup); + if (ret) + return ret; + + hw_ver = readl(qup->base + QUP_HW_VERSION); + dev_dbg(dev, "Revision %x\n", hw_ver); + + io_mode = readl(qup->base + QUP_IO_MODE); + + /* + * The block/fifo size w.r.t. 'actual data' is 1/2 due to 'tag' + * associated with each byte written/received + */ + size_idx = QUP_OUTPUT_BLOCK_SIZE(io_mode); + if (size_idx >= ARRAY_SIZE(blk_sizes)) { + ret = -EIO; + return ret; + } + size = QUP_OUTPUT_FIFO_SIZE(io_mode); + qup->out_fifo_sz = blk_sizes[size_idx] * (2 << size); + + size_idx = QUP_INPUT_BLOCK_SIZE(io_mode); + if (size_idx >= ARRAY_SIZE(blk_sizes)) { + ret = -EIO; + return ret; + } + size = QUP_INPUT_FIFO_SIZE(io_mode); + qup->in_fifo_sz = blk_sizes[size_idx] * (2 << size); + + dev_dbg(dev, "IN:fifo:%d, OUT:fifo:%d\n", qup->in_fifo_sz, + qup->out_fifo_sz); + + return 0; +} + +static int qup_i2c_set_bus_speed(struct udevice *dev, unsigned int clk_freq) +{ + struct qup_i2c_priv *qup = dev_get_priv(dev); + unsigned int src_clk_freq; + int fs_div, hs_div; + + /* We support frequencies up to FAST Mode Plus (1MHz) */ + if (!clk_freq || clk_freq > I2C_SPEED_FAST_PLUS_RATE) { + dev_err(dev, "clock frequency not supported %d\n", clk_freq); + return -EINVAL; + } + + src_clk_freq = clk_get_rate(&qup->iface); + if ((int)src_clk_freq < 0) { + src_clk_freq = DEFAULT_SRC_CLK; + dev_dbg(dev, "using default core freq %d\n", src_clk_freq); + } + + dev_dbg(dev, "src_clk_freq %u\n", src_clk_freq); + dev_dbg(dev, "clk_freq %u\n", clk_freq); + + hs_div = 3; + if (clk_freq <= I2C_SPEED_STANDARD_RATE) { + fs_div = ((src_clk_freq / clk_freq) / 2) - 3; + qup->clk_ctl = (hs_div << 8) | (fs_div & 0xff); + } else { + /* 33%/66% duty cycle */ + fs_div = ((src_clk_freq / clk_freq) - 6) * 2 / 3; + qup->clk_ctl = ((fs_div / 2) << 16) | (hs_div << 8) | (fs_div & 0xff); + } + + dev_dbg(dev, "clk_ctl %u\n", qup->clk_ctl); + + return 0; +} + +/* Probe to see if a chip is present. */ +static int qup_i2c_probe_chip(struct udevice *dev, uint chip_addr, + uint chip_flags) +{ + struct qup_i2c_priv *qup = dev_get_priv(dev); + u32 hw_ver = readl(qup->base + QUP_HW_VERSION); + + return hw_ver ? 0 : -1; +} + +static const struct dm_i2c_ops qup_i2c_ops = { + .xfer = qup_i2c_xfer_v2, + .probe_chip = qup_i2c_probe_chip, + .set_bus_speed = qup_i2c_set_bus_speed, +}; + +static const struct udevice_id qup_i2c_ids[] = { + { .compatible = "qcom,i2c-qup-v2.1.1" }, + { .compatible = "qcom,i2c-qup-v2.2.1" }, + { .compatible = "qcom,i2c-qup" }, + {} +}; + +U_BOOT_DRIVER(i2c_qup) = { + .name = "i2c_qup", + .id = UCLASS_I2C, + .of_match = qup_i2c_ids, + .probe = qup_i2c_probe, + .priv_auto = sizeof(struct qup_i2c_priv), + .ops = &qup_i2c_ops, +};