From: Baihan Li <libaihan@huawei.com> maillist inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/IBSNIA CVE: NA Reference: https://web.git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commi... ---------------------------------------------------------------------- Add dp aux read/write functions. They are basic functions and will be used later. Signed-off-by: Baihan Li <libaihan@huawei.com> Signed-off-by: Yongbang Shi <shiyongbang@huawei.com> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Reviewed-by: Tian Tao <tiantao6@hisilicon.com> Link: https://patchwork.freedesktop.org/patch/msgid/20250103093824.1963816-2-shiyo... Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> --- drivers/gpu/drm/hisilicon/hibmc/Makefile | 3 +- drivers/gpu/drm/hisilicon/hibmc/dp/dp_aux.c | 164 +++++++++++++++++++ drivers/gpu/drm/hisilicon/hibmc/dp/dp_comm.h | 42 +++++ drivers/gpu/drm/hisilicon/hibmc/dp/dp_reg.h | 27 +++ 4 files changed, 235 insertions(+), 1 deletion(-) create mode 100644 drivers/gpu/drm/hisilicon/hibmc/dp/dp_aux.c create mode 100644 drivers/gpu/drm/hisilicon/hibmc/dp/dp_comm.h create mode 100644 drivers/gpu/drm/hisilicon/hibmc/dp/dp_reg.h diff --git a/drivers/gpu/drm/hisilicon/hibmc/Makefile b/drivers/gpu/drm/hisilicon/hibmc/Makefile index d25c75e60d3d..8770ec6dfffd 100644 --- a/drivers/gpu/drm/hisilicon/hibmc/Makefile +++ b/drivers/gpu/drm/hisilicon/hibmc/Makefile @@ -1,4 +1,5 @@ # SPDX-License-Identifier: GPL-2.0-only -hibmc-drm-y := hibmc_drm_drv.o hibmc_drm_de.o hibmc_drm_vdac.o hibmc_drm_i2c.o +hibmc-drm-y := hibmc_drm_drv.o hibmc_drm_de.o hibmc_drm_vdac.o hibmc_drm_i2c.o \ + dp/dp_aux.o obj-$(CONFIG_DRM_HISI_HIBMC) += hibmc-drm.o diff --git a/drivers/gpu/drm/hisilicon/hibmc/dp/dp_aux.c b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_aux.c new file mode 100644 index 000000000000..0a903cce1fa9 --- /dev/null +++ b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_aux.c @@ -0,0 +1,164 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +// Copyright (c) 2024 Hisilicon Limited. + +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/minmax.h> +#include <drm/drm_device.h> +#include <drm/drm_print.h> +#include "dp_comm.h" +#include "dp_reg.h" + +#define HIBMC_AUX_CMD_REQ_LEN GENMASK(7, 4) +#define HIBMC_AUX_CMD_ADDR GENMASK(27, 8) +#define HIBMC_AUX_CMD_I2C_ADDR_ONLY BIT(28) +#define HIBMC_BYTES_IN_U32 4 +#define HIBMC_AUX_I2C_WRITE_SUCCESS 0x1 +#define HIBMC_DP_MIN_PULSE_NUM 0x9 +#define BITS_IN_U8 8 + +static inline void hibmc_dp_aux_reset(struct hibmc_dp_dev *dp) +{ + hibmc_dp_reg_write_field(dp, HIBMC_DP_DPTX_RST_CTRL, HIBMC_DP_CFG_AUX_RST_N, 0x0); + usleep_range(10, 15); + hibmc_dp_reg_write_field(dp, HIBMC_DP_DPTX_RST_CTRL, HIBMC_DP_CFG_AUX_RST_N, 0x1); +} + +static void hibmc_dp_aux_read_data(struct hibmc_dp_dev *dp, u8 *buf, u8 size) +{ + u32 reg_num; + u32 value; + u32 num; + u8 i, j; + + reg_num = DIV_ROUND_UP(size, HIBMC_BYTES_IN_U32); + for (i = 0; i < reg_num; i++) { + /* number of bytes read from a single register */ + num = min(size - i * HIBMC_BYTES_IN_U32, HIBMC_BYTES_IN_U32); + value = readl(dp->base + HIBMC_DP_AUX_RD_DATA0 + i * HIBMC_BYTES_IN_U32); + /* convert the 32-bit value of the register to the buffer. */ + for (j = 0; j < num; j++) + buf[i * HIBMC_BYTES_IN_U32 + j] = value >> (j * BITS_IN_U8); + } +} + +static void hibmc_dp_aux_write_data(struct hibmc_dp_dev *dp, u8 *buf, u8 size) +{ + u32 reg_num; + u32 value; + u32 num; + u8 i, j; + + reg_num = DIV_ROUND_UP(size, HIBMC_BYTES_IN_U32); + for (i = 0; i < reg_num; i++) { + /* number of bytes written to a single register */ + num = min_t(u8, size - i * HIBMC_BYTES_IN_U32, HIBMC_BYTES_IN_U32); + value = 0; + /* obtain the 32-bit value written to a single register. */ + for (j = 0; j < num; j++) + value |= buf[i * HIBMC_BYTES_IN_U32 + j] << (j * BITS_IN_U8); + /* writing data to a single register */ + writel(value, dp->base + HIBMC_DP_AUX_WR_DATA0 + i * HIBMC_BYTES_IN_U32); + } +} + +static u32 hibmc_dp_aux_build_cmd(const struct drm_dp_aux_msg *msg) +{ + u32 aux_cmd = msg->request; + + if (msg->size) + aux_cmd |= FIELD_PREP(HIBMC_AUX_CMD_REQ_LEN, (msg->size - 1)); + else + aux_cmd |= FIELD_PREP(HIBMC_AUX_CMD_I2C_ADDR_ONLY, 1); + + aux_cmd |= FIELD_PREP(HIBMC_AUX_CMD_ADDR, msg->address); + + return aux_cmd; +} + +/* ret >= 0, ret is size; ret < 0, ret is err code */ +static int hibmc_dp_aux_parse_xfer(struct hibmc_dp_dev *dp, struct drm_dp_aux_msg *msg) +{ + u32 buf_data_cnt; + u32 aux_status; + + aux_status = readl(dp->base + HIBMC_DP_AUX_STATUS); + msg->reply = FIELD_GET(HIBMC_DP_CFG_AUX_STATUS, aux_status); + + if (aux_status & HIBMC_DP_CFG_AUX_TIMEOUT) + return -ETIMEDOUT; + + /* only address */ + if (!msg->size) + return 0; + + if (msg->reply != DP_AUX_NATIVE_REPLY_ACK) + return -EIO; + + buf_data_cnt = FIELD_GET(HIBMC_DP_CFG_AUX_READY_DATA_BYTE, aux_status); + + switch (msg->request) { + case DP_AUX_NATIVE_WRITE: + return msg->size; + case DP_AUX_I2C_WRITE | DP_AUX_I2C_MOT: + if (buf_data_cnt == HIBMC_AUX_I2C_WRITE_SUCCESS) + return msg->size; + else + return FIELD_GET(HIBMC_DP_CFG_AUX, aux_status); + case DP_AUX_NATIVE_READ: + case DP_AUX_I2C_READ | DP_AUX_I2C_MOT: + buf_data_cnt--; + if (buf_data_cnt != msg->size) { + /* only the successful part of data is read */ + return -EBUSY; + } + + /* all data is successfully read */ + hibmc_dp_aux_read_data(dp, msg->buffer, msg->size); + return msg->size; + default: + return -EINVAL; + } +} + +/* ret >= 0 ,ret is size; ret < 0, ret is err code */ +static ssize_t hibmc_dp_aux_xfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg) +{ + struct hibmc_dp_dev *dp = container_of(aux, struct hibmc_dp_dev, aux); + u32 aux_cmd; + int ret; + u32 val; /* val will be assigned at the beginning of readl_poll_timeout function */ + + writel(0, dp->base + HIBMC_DP_AUX_WR_DATA0); + writel(0, dp->base + HIBMC_DP_AUX_WR_DATA1); + writel(0, dp->base + HIBMC_DP_AUX_WR_DATA2); + writel(0, dp->base + HIBMC_DP_AUX_WR_DATA3); + + hibmc_dp_aux_write_data(dp, msg->buffer, msg->size); + + aux_cmd = hibmc_dp_aux_build_cmd(msg); + writel(aux_cmd, dp->base + HIBMC_DP_AUX_CMD_ADDR); + + /* enable aux transfer */ + hibmc_dp_reg_write_field(dp, HIBMC_DP_AUX_REQ, HIBMC_DP_CFG_AUX_REQ, 0x1); + ret = readl_poll_timeout(dp->base + HIBMC_DP_AUX_REQ, val, + !(val & HIBMC_DP_CFG_AUX_REQ), 50, 5000); + if (ret) { + hibmc_dp_aux_reset(dp); + return ret; + } + + return hibmc_dp_aux_parse_xfer(dp, msg); +} + +void hibmc_dp_aux_init(struct hibmc_dp_dev *dp) +{ + hibmc_dp_reg_write_field(dp, HIBMC_DP_AUX_REQ, HIBMC_DP_CFG_AUX_SYNC_LEN_SEL, 0x0); + hibmc_dp_reg_write_field(dp, HIBMC_DP_AUX_REQ, HIBMC_DP_CFG_AUX_TIMER_TIMEOUT, 0x1); + hibmc_dp_reg_write_field(dp, HIBMC_DP_AUX_REQ, HIBMC_DP_CFG_AUX_MIN_PULSE_NUM, + HIBMC_DP_MIN_PULSE_NUM); + + dp->aux.transfer = hibmc_dp_aux_xfer; + dp->aux.is_remote = 0; + drm_dp_aux_init(&dp->aux); +} diff --git a/drivers/gpu/drm/hisilicon/hibmc/dp/dp_comm.h b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_comm.h new file mode 100644 index 000000000000..7d3cd32393c0 --- /dev/null +++ b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_comm.h @@ -0,0 +1,42 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* Copyright (c) 2024 Hisilicon Limited. */ + +#ifndef DP_COMM_H +#define DP_COMM_H + +#include <linux/types.h> +#include <linux/bitops.h> +#include <linux/errno.h> +#include <linux/mutex.h> +#include <linux/kernel.h> +#include <linux/bitfield.h> +#include <linux/io.h> +#include <drm/display/drm_dp_helper.h> + +struct hibmc_dp_dev { + struct drm_dp_aux aux; + struct drm_device *dev; + void __iomem *base; + struct mutex lock; /* protects concurrent RW in hibmc_dp_reg_write_field() */ +}; + +#define dp_field_modify(reg_value, mask, val) \ + do { \ + (reg_value) &= ~(mask); \ + (reg_value) |= FIELD_PREP(mask, val); \ + } while (0) \ + +#define hibmc_dp_reg_write_field(dp, offset, mask, val) \ + do { \ + typeof(dp) _dp = dp; \ + typeof(_dp->base) addr = (_dp->base + (offset)); \ + mutex_lock(&_dp->lock); \ + u32 reg_value = readl(addr); \ + dp_field_modify(reg_value, mask, val); \ + writel(reg_value, addr); \ + mutex_unlock(&_dp->lock); \ + } while (0) + +void hibmc_dp_aux_init(struct hibmc_dp_dev *dp); + +#endif diff --git a/drivers/gpu/drm/hisilicon/hibmc/dp/dp_reg.h b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_reg.h new file mode 100644 index 000000000000..f3e6781e111a --- /dev/null +++ b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_reg.h @@ -0,0 +1,27 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* Copyright (c) 2024 Hisilicon Limited. */ + +#ifndef DP_REG_H +#define DP_REG_H + +#define HIBMC_DP_AUX_CMD_ADDR 0x50 +#define HIBMC_DP_AUX_WR_DATA0 0x54 +#define HIBMC_DP_AUX_WR_DATA1 0x58 +#define HIBMC_DP_AUX_WR_DATA2 0x5c +#define HIBMC_DP_AUX_WR_DATA3 0x60 +#define HIBMC_DP_AUX_RD_DATA0 0x64 +#define HIBMC_DP_AUX_REQ 0x74 +#define HIBMC_DP_AUX_STATUS 0x78 +#define HIBMC_DP_DPTX_RST_CTRL 0x700 + +#define HIBMC_DP_CFG_AUX_SYNC_LEN_SEL BIT(1) +#define HIBMC_DP_CFG_AUX_TIMER_TIMEOUT BIT(2) +#define HIBMC_DP_CFG_AUX_MIN_PULSE_NUM GENMASK(13, 9) +#define HIBMC_DP_CFG_AUX_REQ BIT(0) +#define HIBMC_DP_CFG_AUX_RST_N BIT(4) +#define HIBMC_DP_CFG_AUX_TIMEOUT BIT(0) +#define HIBMC_DP_CFG_AUX_READY_DATA_BYTE GENMASK(16, 12) +#define HIBMC_DP_CFG_AUX GENMASK(24, 17) +#define HIBMC_DP_CFG_AUX_STATUS GENMASK(11, 4) + +#endif -- 2.33.0