On Tue, Oct 22, 2024 at 08:41:45PM +0800, Yongbang Shi wrote:
> From: baihan li <libai...@huawei.com>
>
> Add dp aux read/write functions. They are basic functions
> and will be used later.
>
> Signed-off-by: baihan li <libai...@huawei.com>
> ---
> ChangeLog:
> v1 -> v2:
> - using drm_dp_aux frame implement dp aux read and write functions,
> suggested by Jani Nikula.
> - using drm dp header files' dp macros instead, suggested by Andy Yan.
>
> v1:https://lore.kernel.org/all/20240930100610.782363-1-shiyongb...@huawei.com/
> ---
> drivers/gpu/drm/hisilicon/hibmc/Makefile | 3 +-
> drivers/gpu/drm/hisilicon/hibmc/dp/dp_aux.c | 162 +++++++++++++++++++
> drivers/gpu/drm/hisilicon/hibmc/dp/dp_aux.h | 31 ++++
> drivers/gpu/drm/hisilicon/hibmc/dp/dp_comm.h | 74 +++++++++
> drivers/gpu/drm/hisilicon/hibmc/dp/dp_reg.h | 76 +++++++++
> 5 files changed, 345 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_aux.h
> 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..0078cafdf86d
> --- /dev/null
> +++ b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_aux.c
> @@ -0,0 +1,162 @@
> +// 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"
> +#include "dp_aux.h"
> +
> +#define DP_MIN_PULSE_NUM 0x9
> +
> +static void dp_aux_reset(const struct dp_dev *dp)
> +{
> + dp_write_bits(dp->base + DP_DPTX_RST_CTRL, DP_CFG_AUX_RST_N, 0x0);
> + usleep_range(10, 15);
> + dp_write_bits(dp->base + DP_DPTX_RST_CTRL, DP_CFG_AUX_RST_N, 0x1);
> +}
> +
> +static void dp_aux_read_data(struct dp_dev *dp, u8 *buf, u8 size)
> +{
> + u32 reg_num;
> + u32 value;
> + u32 num;
> + u8 i, j;
> +
> + reg_num = round_up(size, AUX_4_BYTE) / AUX_4_BYTE;
> + for (i = 0; i < reg_num; i++) {
> + /* number of bytes read from a single register */
> + num = min(size - i * AUX_4_BYTE, AUX_4_BYTE);
> + value = readl(dp->base + DP_AUX_RD_DATA0 + i * AUX_4_BYTE);
> + /* convert the 32-bit value of the register to the buffer. */
> + for (j = 0; j < num; j++)
> + buf[i * AUX_4_BYTE + j] = value >> (j * AUX_8_BIT);
> + }
> +}
> +
> +static void dp_aux_write_data(struct dp_dev *dp, u8 *buf, u8 size)
> +{
> + u32 reg_num;
> + u32 value;
> + u8 i, j;
> + u32 num;
> +
> + reg_num = round_up(size, AUX_4_BYTE) / AUX_4_BYTE;
> + for (i = 0; i < reg_num; i++) {
> + /* number of bytes written to a single register */
> + num = min_t(u8, size - i * AUX_4_BYTE, AUX_4_BYTE);
> + value = 0;
> + /* obtain the 32-bit value written to a single register. */
> + for (j = 0; j < num; j++)
> + value |= buf[i * AUX_4_BYTE + j] << (j * AUX_8_BIT);
> + /* writing data to a single register */
> + writel(value, dp->base + DP_AUX_WR_DATA0 + i * AUX_4_BYTE);
> + }
> +}
> +
> +static u32 dp_aux_build_cmd(const struct drm_dp_aux_msg *msg)
> +{
> + u32 aux_cmd = msg->request;
> +
> + if (msg->size)
> + aux_cmd |= (msg->size - 1) << AUX_CMD_REQ_LEN_S;
> + else
> + aux_cmd |= 1 << AUX_CMD_I2C_ADDR_ONLY_S;
> +
> + aux_cmd |= msg->address << AUX_CMD_ADDR_S;
> +
> + return aux_cmd;
> +}
> +
> +/* ret >= 0 ,ret is size; ret < 0, ret is err code */
> +static int dp_aux_parse_xfer(struct dp_dev *dp, struct drm_dp_aux_msg *msg)
> +{
> + u32 buf_data_cnt;
> + u32 aux_status;
> + int ret = 0;
> +
> + aux_status = readl(dp->base + DP_AUX_STATUS);
> + msg->reply = FIELD_GET(DP_CFG_AUX_STATUS, aux_status);
> +
> + if (aux_status & DP_CFG_AUX_TIMEOUT)
> + return -ETIMEDOUT;
> +
> + /* only address */
> + if (!msg->size)
> + return 0;
> +
> + if (msg->reply != DP_AUX_NATIVE_REPLY_ACK)
> + return 0;
> +
> + buf_data_cnt = FIELD_GET(DP_CFG_AUX_READY_DATA_BYTE, aux_status);
> +
> + switch (msg->request) {
> + case DP_AUX_NATIVE_WRITE:
> + ret = msg->size;
> + break;
> + case DP_AUX_I2C_WRITE | DP_AUX_I2C_MOT:
> + if (buf_data_cnt == AUX_I2C_WRITE_SUCCESS)
> + ret = msg->size;
> + else if (buf_data_cnt == AUX_I2C_WRITE_PARTIAL_SUCCESS)
> + ret = FIELD_GET(DP_CFG_AUX, aux_status);
> + break;
> + case DP_AUX_NATIVE_READ:
> + case DP_AUX_I2C_READ | DP_AUX_I2C_MOT:
> + buf_data_cnt--;
> + /* only the successful part of data is read */
> + if (buf_data_cnt != msg->size) {
> + ret = -EBUSY;
> + } else { /* all data is successfully read */
> + dp_aux_read_data(dp, msg->buffer, msg->size);
> + ret = msg->size;
> + }
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + return ret;
> +}
> +
> +/* ret >= 0 ,ret is size; ret < 0, ret is err code */
> +static ssize_t dp_aux_xfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg
> *msg)
> +{
> + struct dp_dev *dp = container_of(aux, struct 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 + DP_AUX_WR_DATA0);
> + writel(0, dp->base + DP_AUX_WR_DATA1);
> + writel(0, dp->base + DP_AUX_WR_DATA2);
> + writel(0, dp->base + DP_AUX_WR_DATA3);
> +
> + dp_aux_write_data(dp, msg->buffer, msg->size);
> +
> + aux_cmd = dp_aux_build_cmd(msg);
> + writel(aux_cmd, dp->base + DP_AUX_CMD_ADDR);
> +
> + /* enable aux transfer */
> + dp_write_bits(dp->base + DP_AUX_REQ, DP_CFG_AUX_REQ, 0x1);
> + ret = readl_poll_timeout(dp->base + DP_AUX_REQ, val, !(val &
> DP_CFG_AUX_REQ), 50, 5000);
> + if (ret) {
> + dp_aux_reset(dp);
> + return ret;
> + }
> +
> + return dp_aux_parse_xfer(dp, msg);
> +}
> +
> +void dp_aux_init(struct dp_dev *dp)
> +{
> + dp_write_bits(dp->base + DP_AUX_REQ, DP_CFG_AUX_SYNC_LEN_SEL, 0x0);
> + dp_write_bits(dp->base + DP_AUX_REQ, DP_CFG_AUX_TIMER_TIMEOUT, 0x1);
> + dp_write_bits(dp->base + DP_AUX_REQ, DP_CFG_AUX_MIN_PULSE_NUM,
> DP_MIN_PULSE_NUM);
> +
> + dp->aux.transfer = dp_aux_xfer;
> + dp->aux.is_remote = 0;
> + drm_dp_aux_init(&dp->aux);
> +}
> diff --git a/drivers/gpu/drm/hisilicon/hibmc/dp/dp_aux.h
> b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_aux.h
> new file mode 100644
> index 000000000000..6f95a3750d60
> --- /dev/null
> +++ b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_aux.h
> @@ -0,0 +1,31 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/* Copyright (c) 2024 Hisilicon Limited. */
> +
> +#ifndef DP_AUX_H
> +#define DP_AUX_H
> +
> +#include <linux/bitops.h>
> +#include "dp_comm.h"
> +
> +#define AUX_I2C_WRITE_SUCCESS 0x1
> +#define AUX_I2C_WRITE_PARTIAL_SUCCESS 0x2
> +
> +#define EQ_MAX_RETRY 5
unused
> +
> +#define DP_CFG_AUX_S 17
> +#define DP_CFG_AUX_STATUS_S 4
Both are unused
> +
> +#define AUX_4_BYTE 4
> +#define AUX_4_BIT 4
> +#define AUX_8_BIT 8
AUX_4_BIT is unused. For other defines I think it's better to provide
sensible names. BITS_IN_U32, BYTES_IN_U32
> +
> +#define AUX_READY_DATA_BYTE_S 12
unused
> +
> +/* aux_cmd_addr register shift */
> +#define AUX_CMD_REQ_LEN_S 4
> +#define AUX_CMD_ADDR_S 8
> +#define AUX_CMD_I2C_ADDR_ONLY_S 28
Please use FIELD_PREP instead of definig shifts (and shift is usally
_SHIFT, not _S)
> +
> +void dp_aux_init(struct dp_dev *dp);
> +
> +#endif
> 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..26d97929dc06
> --- /dev/null
> +++ b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_comm.h
> @@ -0,0 +1,74 @@
> +/* 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>
> +
> +#define REG_LENGTH 32
> +
> +static inline u32 dp_read_bits(void __iomem *addr, u32 bit_mask)
> +{
> + u32 reg_val;
> +
> + reg_val = readl(addr);
> +
> + return (reg_val & bit_mask) >> __ffs(bit_mask);
FIELD_GET
> +}
> +
> +static inline void dp_write_bits(void __iomem *addr, u32 bit_mask, u32 val)
> +{
> + u32 reg_val;
> +
> + reg_val = readl(addr);
> + reg_val &= ~bit_mask;
> + reg_val |= (val << __ffs(bit_mask)) & bit_mask;
FIELD_PREP
> + writel(reg_val, addr);
How is this protected from concurrent RMW cycles?
> +}
> +
> +enum dpcd_revision {
> + DPCD_REVISION_10 = 0x10,
> + DPCD_REVISION_11,
> + DPCD_REVISION_12,
> + DPCD_REVISION_13,
> + DPCD_REVISION_14,
Any reason for ignoring defines in drm_dp.h?
> +};
> +
> +struct link_status {
> + bool clock_recovered;
> + bool channel_equalized;
> + u8 cr_done_lanes;
> +};
> +
> +struct link_cap {
> + enum dpcd_revision rx_dpcd_revision;
> + u8 link_rate;
> + u8 lanes;
> + bool is_tps3;
> + bool is_tps4;
> +};
> +
> +struct hibmc_dp_link {
> + struct link_status status;
> + u8 *train_set;
> + struct link_cap cap;
> +};
> +
> +struct dp_dev {
> + struct hibmc_dp_link link;
> + struct drm_dp_aux aux;
> + struct drm_device *dev;
> + void __iomem *base;
> + u8 dpcd[DP_RECEIVER_CAP_SIZE];
> +};
> +
> +#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..3dcb847057a4
> --- /dev/null
> +++ b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_reg.h
> @@ -0,0 +1,76 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/* Copyright (c) 2024 Hisilicon Limited. */
> +
> +#ifndef DP_REG_H
> +#define DP_REG_H
> +
> +#define DP_AUX_CMD_ADDR 0x50
> +#define DP_AUX_WR_DATA0 0x54
> +#define DP_AUX_WR_DATA1 0x58
> +#define DP_AUX_WR_DATA2 0x5c
> +#define DP_AUX_WR_DATA3 0x60
> +#define DP_AUX_RD_DATA0 0x64
> +#define DP_AUX_REQ 0x74
> +#define DP_AUX_STATUS 0x78
> +#define DP_PHYIF_CTRL0 0xa0
> +#define DP_VIDEO_CTRL 0x100
> +#define DP_VIDEO_CONFIG0 0x104
> +#define DP_VIDEO_CONFIG1 0x108
> +#define DP_VIDEO_CONFIG2 0x10c
> +#define DP_VIDEO_CONFIG3 0x110
> +#define DP_VIDEO_PACKET 0x114
> +#define DP_VIDEO_MSA0 0x118
> +#define DP_VIDEO_MSA1 0x11c
> +#define DP_VIDEO_MSA2 0x120
> +#define DP_VIDEO_HORIZONTAL_SIZE 0X124
> +#define DP_TIMING_GEN_CONFIG0 0x26c
> +#define DP_TIMING_GEN_CONFIG2 0x274
> +#define DP_TIMING_GEN_CONFIG3 0x278
> +#define DP_HDCP_CFG 0x600
> +#define DP_INTR_ENABLE 0x720
> +#define DP_INTR_ORIGINAL_STATUS 0x728
> +#define DP_DPTX_RST_CTRL 0x700
> +#define DP_DPTX_CLK_CTRL 0x704
> +#define DP_DPTX_GCTL0 0x708
> +#define DP_TIMING_MODEL_CTRL 0x884
> +#define DP_TIMING_SYNC_CTRL 0xFF0
> +
> +#define DP_CFG_AUX_SYNC_LEN_SEL BIT(1)
> +#define DP_CFG_AUX_TIMER_TIMEOUT BIT(2)
> +#define DP_CFG_STREAM_FRAME_MODE BIT(6)
> +#define DP_CFG_AUX_MIN_PULSE_NUM GENMASK(13, 9)
> +#define DP_CFG_LANE_DATA_EN GENMASK(11, 8)
> +#define DP_CFG_PHY_LANE_NUM GENMASK(2, 1)
> +#define DP_CFG_AUX_REQ BIT(0)
> +#define DP_CFG_AUX_RST_N BIT(4)
> +#define DP_CFG_AUX_TIMEOUT BIT(0)
> +#define DP_CFG_AUX_READY_DATA_BYTE GENMASK(16, 12)
> +#define DP_CFG_AUX GENMASK(24, 17)
> +#define DP_CFG_AUX_STATUS GENMASK(11, 4)
> +#define DP_CFG_SCRAMBLE_EN BIT(0)
> +#define DP_CFG_PAT_SEL GENMASK(7, 4)
> +#define DP_CFG_TIMING_GEN0_HACTIVE GENMASK(31, 16)
> +#define DP_CFG_TIMING_GEN0_HBLANK GENMASK(15, 0)
> +#define DP_CFG_TIMING_GEN0_VACTIVE GENMASK(31, 16)
> +#define DP_CFG_TIMING_GEN0_VBLANK GENMASK(15, 0)
> +#define DP_CFG_TIMING_GEN0_VFRONT_PORCH GENMASK(31, 16)
> +#define DP_CFG_STREAM_HACTIVE GENMASK(31, 16)
> +#define DP_CFG_STREAM_HBLANK GENMASK(15, 0)
> +#define DP_CFG_STREAM_HSYNC_WIDTH GENMASK(15, 0)
> +#define DP_CFG_STREAM_VACTIVE GENMASK(31, 16)
> +#define DP_CFG_STREAM_VBLANK GENMASK(15, 0)
> +#define DP_CFG_STREAM_VFRONT_PORCH GENMASK(31, 16)
> +#define DP_CFG_STREAM_VSYNC_WIDTH GENMASK(15, 0)
> +#define DP_CFG_STREAM_VSTART GENMASK(31, 16)
> +#define DP_CFG_STREAM_HSTART GENMASK(15, 0)
> +#define DP_CFG_STREAM_VSYNC_POLARITY BIT(8)
> +#define DP_CFG_STREAM_HSYNC_POLARITY BIT(7)
> +#define DP_CFG_STREAM_RGB_ENABLE BIT(1)
> +#define DP_CFG_STREAM_VIDEO_MAPPING GENMASK(5, 2)
> +#define DP_CFG_PIXEL_NUM_TIMING_MODE_SEL1 GENMASK(31, 16)
> +#define DP_CFG_STREAM_TU_SYMBOL_SIZE GENMASK(5, 0)
> +#define DP_CFG_STREAM_TU_SYMBOL_FRAC_SIZE GENMASK(9, 6)
> +#define DP_CFG_STREAM_HTOTAL_SIZE GENMASK(31, 16)
> +#define DP_CFG_STREAM_HBLANK_SIZE GENMASK(15, 0)
> +
> +#endif
> --
> 2.33.0
>
--
With best wishes
Dmitry
