On Fri, Nov 01, 2024 at 06:50:25PM +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>
Is this a proper capitalization of your names? Usually the first letter
of each of them is capital.
---
ChangeLog:
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 | 162 ++++++++++++++++++
drivers/gpu/drm/hisilicon/hibmc/dp/dp_aux.h | 23 +++
drivers/gpu/drm/hisilicon/hibmc/dp/dp_comm.h | 58 +++++++
.../gpu/drm/hisilicon/hibmc/dp/dp_config.h | 19 ++
drivers/gpu/drm/hisilicon/hibmc/dp/dp_reg.h | 27 +++
6 files changed, 291 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_config.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..49ecda672109
--- /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 hibmc_dp_aux_reset(const struct dp_dev *dp)
+{
+ dp_reg_write_field(dp->base + DP_DPTX_RST_CTRL, DP_CFG_AUX_RST_N, 0x0);
+ usleep_range(10, 15);
+ dp_reg_write_field(dp->base + DP_DPTX_RST_CTRL, DP_CFG_AUX_RST_N, 0x1);
+}
+
+static void hibmc_dp_aux_read_data(struct dp_dev *dp, u8 *buf, u8 size)
+{
+ u32 reg_num;
+ u32 value;
+ u32 num;
+ u8 i, j;
+
+ reg_num = DIV_ROUND_UP(size, BYTES_IN_U32);
+ for (i = 0; i < reg_num; i++) {
+ /* number of bytes read from a single register */
+ num = min(size - i * BYTES_IN_U32, BYTES_IN_U32);
+ value = readl(dp->base + DP_AUX_RD_DATA0 + i * BYTES_IN_U32);
+ /* convert the 32-bit value of the register to the buffer. */
+ for (j = 0; j < num; j++)
+ buf[i * BYTES_IN_U32 + j] = value >> (j * BITS_IN_U8);
put_unaligned_le32()
+ }
+}
+
+static void hibmc_dp_aux_write_data(struct dp_dev *dp, u8 *buf, u8 size)
+{
+ u32 reg_num;
+ u32 value;
+ u8 i, j;
+ u32 num;
+
+ reg_num = DIV_ROUND_UP(size, BYTES_IN_U32);
+ for (i = 0; i < reg_num; i++) {
+ /* number of bytes written to a single register */
+ num = min_t(u8, size - i * BYTES_IN_U32, BYTES_IN_U32);
+ value = 0;
+ /* obtain the 32-bit value written to a single register. */
+ for (j = 0; j < num; j++)
+ value |= buf[i * BYTES_IN_U32 + j] << (j * BITS_IN_U8);
get_unaligned_le32()
+ /* writing data to a single register */
+ writel(value, dp->base + DP_AUX_WR_DATA0 + i * 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(AUX_CMD_REQ_LEN, (msg->size - 1));
+ else
+ aux_cmd |= FIELD_PREP(AUX_CMD_I2C_ADDR_ONLY, 1);
+
+ aux_cmd |= FIELD_PREP(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 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;
Should this be an error instead?
+
+ 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);
Replace all ret= with returns. Nothing happens after the switch-case, so
return right away.
+ 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 */
Nit: only a part of data wass read successfully.
move the comment into the underlying `
+ if (buf_data_cnt != msg->size) {
+ ret = -EBUSY;
+ } else { /* all data is successfully read */
+ hibmc_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 hibmc_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);
+
+ hibmc_dp_aux_write_data(dp, msg->buffer, msg->size);
+
+ aux_cmd = hibmc_dp_aux_build_cmd(msg);
+ writel(aux_cmd, dp->base + DP_AUX_CMD_ADDR);
+
+ /* enable aux transfer */
+ dp_reg_write_field(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) {
+ hibmc_dp_aux_reset(dp);
+ return ret;
+ }
+
+ return hibmc_dp_aux_parse_xfer(dp, msg);
+}
+
+void hibmc_dp_aux_init(struct dp_dev *dp)
+{
+ dp_reg_write_field(dp->base + DP_AUX_REQ, DP_CFG_AUX_SYNC_LEN_SEL, 0x0);
+ dp_reg_write_field(dp->base + DP_AUX_REQ, DP_CFG_AUX_TIMER_TIMEOUT, 0x1);
+ dp_reg_write_field(dp->base + DP_AUX_REQ, DP_CFG_AUX_MIN_PULSE_NUM, 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_aux.h b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_aux.h
new file mode 100644
index 000000000000..794bb0482ea7
--- /dev/null
+++ b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_aux.h
@@ -0,0 +1,23 @@
+/* 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
Move to the source file
+#define AUX_I2C_WRITE_PARTIAL_SUCCESS 0x2
Ditto
+#define EQ_MAX_RETRY 5
Unused
+#define BYTES_IN_U32 4
+#define BITS_IN_U8 8
This one will go away after using foo_unaligned_le32
+
+/* aux_cmd_addr register shift */
+#define AUX_CMD_REQ_LEN GENMASK(7, 4)
+#define AUX_CMD_ADDR GENMASK(27, 8)
+#define AUX_CMD_I2C_ADDR_ONLY BIT(28)
These can go to the source file too. Or to dp_reg.h. Don't spawn that
all over the place.
+
+void hibmc_dp_aux_init(struct dp_dev *dp);
As the header becomes nearly empty, merge the remnants to a generic
header.
+
+#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..61a59fd59962
--- /dev/null
+++ b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_comm.h
@@ -0,0 +1,58 @@
+/* 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 dp_reg_read_field(addr, mask) \
These are still using dp_ prefix. Also using static inline functions
might be easier to handle.
+ FIELD_GET(mask, readl(addr))
+
+#define dp_field_modify(reg_value, mask, value) ({ \
+ (reg_value) &= ~(mask); \
+ (reg_value) |= FIELD_PREP(mask, value); })
+
+#define dp_reg_write_field(addr, mask, val) ({ \
+ typeof(addr) _addr = (addr); \
+ u32 _value = readl(_addr); \
+ dp_field_modify(_value, mask, val); \
+ writel(_value, _addr); })
I'm still very unsatisfied here. You have an RMW code with no locking.
If anything writes to the same location at the same time, the driver is
busted.
+
+struct link_status {
It is hibmc-specific, so please prefix accordingly.
+ bool clock_recovered;
+ bool channel_equalized;
+ u8 cr_done_lanes;
+};
+
+struct link_cap {
+ int 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;
+};
Please don't define the structures/fields that are not used by the
patch. Introduce them when required.
+
+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_config.h b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_config.h
new file mode 100644
index 000000000000..0b965e6ba7b3
--- /dev/null
+++ b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_config.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* Copyright (c) 2024 Hisilicon Limited. */
+
+#ifndef DP_CONFIG_H
+#define DP_CONFIG_H
+
+#define DP_BPP 24
+#define DP_SYMBOL_PER_FCLK 4
+#define DP_MSA1 0x20
+#define DP_MSA2 0x845c00
+#define DP_OFFSET 0x1e0000
+#define DP_HDCP 0x2
+#define DP_INT_RST 0xffff
+#define DP_DPTX_RST 0x3ff
+#define DP_CLK_EN 0x7
+#define DP_SYNC_EN_MASK 0x3
+#define DP_LINK_RATE_CAL 27
+
+#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..83cf0cc06ae2
--- /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 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_DPTX_RST_CTRL 0x700
+
+#define DP_CFG_AUX_SYNC_LEN_SEL BIT(1)
+#define DP_CFG_AUX_TIMER_TIMEOUT BIT(2)
+#define DP_CFG_AUX_MIN_PULSE_NUM GENMASK(13, 9)
+#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)
+
+#endif
--
2.33.0
