On Mon, Nov 18, 2024 at 10:28:01PM +0800, Yongbang Shi wrote: > From: baihan li <libaihan@xxxxxxxxxx> > > Add dp aux read/write functions. They are basic functions > and will be used later. > > Signed-off-by: Baihan Li <libaihan@xxxxxxxxxx> > Signed-off-by: Yongbang Shi <shiyongbang@xxxxxxxxxx> > --- > ChangeLog: > v4 -> v5: > - fixing build errors reported by kernel test robot <lkp@xxxxxxxxx> > Closes: https://lore.kernel.org/oe-kbuild-all/202411131438.RZWYrWTE-lkp@xxxxxxxxx/ > v3 -> v4: > - retun error codes in result incorrect branch, suggested by Dmitry Baryshkov. > - replacing all ret= with returns, suggested by Dmitry Baryshkov. > - moving the comment below the judgment statement, suggested by Dmitry Baryshkov. > - moving definations to the source file and clearing headers, suggested by Dmitry Baryshkov. > - reanaming dp_prefix to hibmc_dp_prefix, suggested by Dmitry Baryshkov. > - changing hibmc_dp_reg_write_field to static inline and lock, suggested by Dmitry Baryshkov. > - moving some structs to later patch, suggested by Dmitry Baryshkov. > v2 -> v3: > - put the macro definations in latter patch where they are actually used, suggested by Dmitry Baryshkov. > - rename some macro definations to make them sensible, suggested by Dmitry Baryshkov. > - using FIELD_PREP and FIELD_GET, suggested by Dmitry Baryshkov. > - using DP_DPCD_REV_foo, suggested by Dmitry Baryshkov. > - fix build errors reported by kernel test robot <lkp@xxxxxxxxx> > Closes: https://lore.kernel.org/oe-kbuild-all/202410250305.UHKDhtxy-lkp@xxxxxxxxx/ > 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-shiyongbang@xxxxxxxxxx/ > --- > 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 | 38 +++++ > drivers/gpu/drm/hisilicon/hibmc/dp/dp_reg.h | 27 +++ > 4 files changed, 231 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..16bdfefbf255 > --- /dev/null > +++ b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_aux.c > @@ -0,0 +1,164 @@ > +// SPDX-License-Identifier: GPL-2.0-or-laterHIBMC_BYTES_IN_U32 > +// 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..ce3b6fa4ea9e > --- /dev/null > +++ b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_comm.h > @@ -0,0 +1,38 @@ > +/* 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) ({ \ > + (reg_value) &= ~(mask); \ > + (reg_value) |= FIELD_PREP(mask, val); }) do { ... } while (0) or static inline. Or just inline into the calling function, if there is just one place where it is used. > + > +#define hibmc_dp_reg_write_field(dp, offset, mask, val) ({ \ > + 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); }) I'd prefer a static inline function. Other than that: Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> > + > +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 > -- With best wishes Dmitry
