| From 8c72ef27d44f3339fb9b8261b81b5dea5e05910a Mon Sep 17 00:00:00 2001 |
| From: =?UTF-8?q?Noralf=20Tr=C3=B8nnes?= <noralf@tronnes.org> |
| Date: Fri, 22 Feb 2019 13:43:29 +0100 |
| Subject: tinydrm/mipi-dbi: Use dma-safe buffers for all SPI transfers |
| MIME-Version: 1.0 |
| Content-Type: text/plain; charset=UTF-8 |
| Content-Transfer-Encoding: 8bit |
| |
| [ Upstream commit a89bfc5d9a0732d84b4de311e27133daa0586316 ] |
| |
| Buffers passed to spi_sync() must be dma-safe even for tiny buffers since |
| some SPI controllers use DMA for all transfers. |
| |
| Example splat with CONFIG_DMA_API_DEBUG enabled: |
| |
| [ 23.750467] DMA-API: dw_dmac_pci 0000:00:15.0: device driver maps memory from stack [probable addr=000000001e49185d] |
| [ 23.750529] WARNING: CPU: 1 PID: 1296 at kernel/dma/debug.c:1161 check_for_stack+0xb7/0x190 |
| [ 23.750533] Modules linked in: mmc_block(+) spi_pxa2xx_platform(+) pwm_lpss_pci pwm_lpss spi_pxa2xx_pci sdhci_pci cqhci intel_mrfld_pwrbtn extcon_intel_mrfld sdhci intel_mrfld_adc led_class mmc_core ili9341 mipi_dbi tinydrm backlight ti_ads7950 industrialio_triggered_buffer kfifo_buf intel_soc_pmic_mrfld hci_uart btbcm |
| [ 23.750599] CPU: 1 PID: 1296 Comm: modprobe Not tainted 5.0.0-rc7+ #236 |
| [ 23.750605] Hardware name: Intel Corporation Merrifield/BODEGA BAY, BIOS 542 2015.01.21:18.19.48 |
| [ 23.750620] RIP: 0010:check_for_stack+0xb7/0x190 |
| [ 23.750630] Code: 8b 6d 50 4d 85 ed 75 04 4c 8b 6d 10 48 89 ef e8 2f 8b 44 00 48 89 c6 4a 8d 0c 23 4c 89 ea 48 c7 c7 88 d0 82 b4 e8 40 7c f9 ff <0f> 0b 8b 05 79 00 4b 01 85 c0 74 07 5b 5d 41 5c 41 5d c3 8b 05 54 |
| [ 23.750637] RSP: 0000:ffff97bbc0292fa0 EFLAGS: 00010286 |
| [ 23.750646] RAX: 0000000000000000 RBX: ffff97bbc0290000 RCX: 0000000000000006 |
| [ 23.750652] RDX: 0000000000000007 RSI: 0000000000000002 RDI: ffff94b33e115450 |
| [ 23.750658] RBP: ffff94b33c8578b0 R08: 0000000000000002 R09: 00000000000201c0 |
| [ 23.750664] R10: 00000006ecb0ccc6 R11: 0000000000034f38 R12: 000000000000316c |
| [ 23.750670] R13: ffff94b33c84b250 R14: ffff94b33dedd5a0 R15: 0000000000000001 |
| [ 23.750679] FS: 0000000000000000(0000) GS:ffff94b33e100000(0063) knlGS:00000000f7faf690 |
| [ 23.750686] CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 |
| [ 23.750691] CR2: 00000000f7f54faf CR3: 000000000722c000 CR4: 00000000001006e0 |
| [ 23.750696] Call Trace: |
| [ 23.750713] debug_dma_map_sg+0x100/0x340 |
| [ 23.750727] ? dma_direct_map_sg+0x3b/0xb0 |
| [ 23.750739] spi_map_buf+0x25a/0x300 |
| [ 23.750751] __spi_pump_messages+0x2a4/0x680 |
| [ 23.750762] __spi_sync+0x1dd/0x1f0 |
| [ 23.750773] spi_sync+0x26/0x40 |
| [ 23.750790] mipi_dbi_typec3_command_read+0x14d/0x240 [mipi_dbi] |
| [ 23.750802] ? spi_finalize_current_transfer+0x10/0x10 |
| [ 23.750821] mipi_dbi_typec3_command+0x1bc/0x1d0 [mipi_dbi] |
| |
| Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> |
| Signed-off-by: Noralf TrΓΈnnes <noralf@tronnes.org> |
| Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> |
| Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> |
| Link: https://patchwork.freedesktop.org/patch/msgid/20190222124329.23046-1-noralf@tronnes.org |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| drivers/gpu/drm/tinydrm/ili9225.c | 6 ++-- |
| drivers/gpu/drm/tinydrm/mipi-dbi.c | 58 +++++++++++++++++++++--------- |
| include/drm/tinydrm/mipi-dbi.h | 5 +-- |
| 3 files changed, 48 insertions(+), 21 deletions(-) |
| |
| diff --git a/drivers/gpu/drm/tinydrm/ili9225.c b/drivers/gpu/drm/tinydrm/ili9225.c |
| index 43a3b68d90a20..998d75be9e16f 100644 |
| --- a/drivers/gpu/drm/tinydrm/ili9225.c |
| +++ b/drivers/gpu/drm/tinydrm/ili9225.c |
| @@ -301,7 +301,7 @@ static void ili9225_pipe_disable(struct drm_simple_display_pipe *pipe) |
| mipi->enabled = false; |
| } |
| |
| -static int ili9225_dbi_command(struct mipi_dbi *mipi, u8 cmd, u8 *par, |
| +static int ili9225_dbi_command(struct mipi_dbi *mipi, u8 *cmd, u8 *par, |
| size_t num) |
| { |
| struct spi_device *spi = mipi->spi; |
| @@ -311,11 +311,11 @@ static int ili9225_dbi_command(struct mipi_dbi *mipi, u8 cmd, u8 *par, |
| |
| gpiod_set_value_cansleep(mipi->dc, 0); |
| speed_hz = mipi_dbi_spi_cmd_max_speed(spi, 1); |
| - ret = tinydrm_spi_transfer(spi, speed_hz, NULL, 8, &cmd, 1); |
| + ret = tinydrm_spi_transfer(spi, speed_hz, NULL, 8, cmd, 1); |
| if (ret || !num) |
| return ret; |
| |
| - if (cmd == ILI9225_WRITE_DATA_TO_GRAM && !mipi->swap_bytes) |
| + if (*cmd == ILI9225_WRITE_DATA_TO_GRAM && !mipi->swap_bytes) |
| bpw = 16; |
| |
| gpiod_set_value_cansleep(mipi->dc, 1); |
| diff --git a/drivers/gpu/drm/tinydrm/mipi-dbi.c b/drivers/gpu/drm/tinydrm/mipi-dbi.c |
| index 918f77c7de34e..295cbcbc2bb65 100644 |
| --- a/drivers/gpu/drm/tinydrm/mipi-dbi.c |
| +++ b/drivers/gpu/drm/tinydrm/mipi-dbi.c |
| @@ -153,16 +153,42 @@ EXPORT_SYMBOL(mipi_dbi_command_read); |
| */ |
| int mipi_dbi_command_buf(struct mipi_dbi *mipi, u8 cmd, u8 *data, size_t len) |
| { |
| + u8 *cmdbuf; |
| int ret; |
| |
| + /* SPI requires dma-safe buffers */ |
| + cmdbuf = kmemdup(&cmd, 1, GFP_KERNEL); |
| + if (!cmdbuf) |
| + return -ENOMEM; |
| + |
| mutex_lock(&mipi->cmdlock); |
| - ret = mipi->command(mipi, cmd, data, len); |
| + ret = mipi->command(mipi, cmdbuf, data, len); |
| mutex_unlock(&mipi->cmdlock); |
| |
| + kfree(cmdbuf); |
| + |
| return ret; |
| } |
| EXPORT_SYMBOL(mipi_dbi_command_buf); |
| |
| +/* This should only be used by mipi_dbi_command() */ |
| +int mipi_dbi_command_stackbuf(struct mipi_dbi *mipi, u8 cmd, u8 *data, size_t len) |
| +{ |
| + u8 *buf; |
| + int ret; |
| + |
| + buf = kmemdup(data, len, GFP_KERNEL); |
| + if (!buf) |
| + return -ENOMEM; |
| + |
| + ret = mipi_dbi_command_buf(mipi, cmd, buf, len); |
| + |
| + kfree(buf); |
| + |
| + return ret; |
| +} |
| +EXPORT_SYMBOL(mipi_dbi_command_stackbuf); |
| + |
| /** |
| * mipi_dbi_buf_copy - Copy a framebuffer, transforming it if necessary |
| * @dst: The destination buffer |
| @@ -774,18 +800,18 @@ static int mipi_dbi_spi1_transfer(struct mipi_dbi *mipi, int dc, |
| return 0; |
| } |
| |
| -static int mipi_dbi_typec1_command(struct mipi_dbi *mipi, u8 cmd, |
| +static int mipi_dbi_typec1_command(struct mipi_dbi *mipi, u8 *cmd, |
| u8 *parameters, size_t num) |
| { |
| - unsigned int bpw = (cmd == MIPI_DCS_WRITE_MEMORY_START) ? 16 : 8; |
| + unsigned int bpw = (*cmd == MIPI_DCS_WRITE_MEMORY_START) ? 16 : 8; |
| int ret; |
| |
| - if (mipi_dbi_command_is_read(mipi, cmd)) |
| + if (mipi_dbi_command_is_read(mipi, *cmd)) |
| return -ENOTSUPP; |
| |
| - MIPI_DBI_DEBUG_COMMAND(cmd, parameters, num); |
| + MIPI_DBI_DEBUG_COMMAND(*cmd, parameters, num); |
| |
| - ret = mipi_dbi_spi1_transfer(mipi, 0, &cmd, 1, 8); |
| + ret = mipi_dbi_spi1_transfer(mipi, 0, cmd, 1, 8); |
| if (ret || !num) |
| return ret; |
| |
| @@ -794,7 +820,7 @@ static int mipi_dbi_typec1_command(struct mipi_dbi *mipi, u8 cmd, |
| |
| /* MIPI DBI Type C Option 3 */ |
| |
| -static int mipi_dbi_typec3_command_read(struct mipi_dbi *mipi, u8 cmd, |
| +static int mipi_dbi_typec3_command_read(struct mipi_dbi *mipi, u8 *cmd, |
| u8 *data, size_t len) |
| { |
| struct spi_device *spi = mipi->spi; |
| @@ -803,7 +829,7 @@ static int mipi_dbi_typec3_command_read(struct mipi_dbi *mipi, u8 cmd, |
| struct spi_transfer tr[2] = { |
| { |
| .speed_hz = speed_hz, |
| - .tx_buf = &cmd, |
| + .tx_buf = cmd, |
| .len = 1, |
| }, { |
| .speed_hz = speed_hz, |
| @@ -821,8 +847,8 @@ static int mipi_dbi_typec3_command_read(struct mipi_dbi *mipi, u8 cmd, |
| * Support non-standard 24-bit and 32-bit Nokia read commands which |
| * start with a dummy clock, so we need to read an extra byte. |
| */ |
| - if (cmd == MIPI_DCS_GET_DISPLAY_ID || |
| - cmd == MIPI_DCS_GET_DISPLAY_STATUS) { |
| + if (*cmd == MIPI_DCS_GET_DISPLAY_ID || |
| + *cmd == MIPI_DCS_GET_DISPLAY_STATUS) { |
| if (!(len == 3 || len == 4)) |
| return -EINVAL; |
| |
| @@ -852,7 +878,7 @@ static int mipi_dbi_typec3_command_read(struct mipi_dbi *mipi, u8 cmd, |
| data[i] = (buf[i] << 1) | !!(buf[i + 1] & BIT(7)); |
| } |
| |
| - MIPI_DBI_DEBUG_COMMAND(cmd, data, len); |
| + MIPI_DBI_DEBUG_COMMAND(*cmd, data, len); |
| |
| err_free: |
| kfree(buf); |
| @@ -860,7 +886,7 @@ static int mipi_dbi_typec3_command_read(struct mipi_dbi *mipi, u8 cmd, |
| return ret; |
| } |
| |
| -static int mipi_dbi_typec3_command(struct mipi_dbi *mipi, u8 cmd, |
| +static int mipi_dbi_typec3_command(struct mipi_dbi *mipi, u8 *cmd, |
| u8 *par, size_t num) |
| { |
| struct spi_device *spi = mipi->spi; |
| @@ -868,18 +894,18 @@ static int mipi_dbi_typec3_command(struct mipi_dbi *mipi, u8 cmd, |
| u32 speed_hz; |
| int ret; |
| |
| - if (mipi_dbi_command_is_read(mipi, cmd)) |
| + if (mipi_dbi_command_is_read(mipi, *cmd)) |
| return mipi_dbi_typec3_command_read(mipi, cmd, par, num); |
| |
| - MIPI_DBI_DEBUG_COMMAND(cmd, par, num); |
| + MIPI_DBI_DEBUG_COMMAND(*cmd, par, num); |
| |
| gpiod_set_value_cansleep(mipi->dc, 0); |
| speed_hz = mipi_dbi_spi_cmd_max_speed(spi, 1); |
| - ret = tinydrm_spi_transfer(spi, speed_hz, NULL, 8, &cmd, 1); |
| + ret = tinydrm_spi_transfer(spi, speed_hz, NULL, 8, cmd, 1); |
| if (ret || !num) |
| return ret; |
| |
| - if (cmd == MIPI_DCS_WRITE_MEMORY_START && !mipi->swap_bytes) |
| + if (*cmd == MIPI_DCS_WRITE_MEMORY_START && !mipi->swap_bytes) |
| bpw = 16; |
| |
| gpiod_set_value_cansleep(mipi->dc, 1); |
| diff --git a/include/drm/tinydrm/mipi-dbi.h b/include/drm/tinydrm/mipi-dbi.h |
| index f4ec2834bc229..7dfa67a15a04e 100644 |
| --- a/include/drm/tinydrm/mipi-dbi.h |
| +++ b/include/drm/tinydrm/mipi-dbi.h |
| @@ -43,7 +43,7 @@ struct mipi_dbi { |
| struct spi_device *spi; |
| bool enabled; |
| struct mutex cmdlock; |
| - int (*command)(struct mipi_dbi *mipi, u8 cmd, u8 *param, size_t num); |
| + int (*command)(struct mipi_dbi *mipi, u8 *cmd, u8 *param, size_t num); |
| const u8 *read_commands; |
| struct gpio_desc *dc; |
| u16 *tx_buf; |
| @@ -82,6 +82,7 @@ u32 mipi_dbi_spi_cmd_max_speed(struct spi_device *spi, size_t len); |
| |
| int mipi_dbi_command_read(struct mipi_dbi *mipi, u8 cmd, u8 *val); |
| int mipi_dbi_command_buf(struct mipi_dbi *mipi, u8 cmd, u8 *data, size_t len); |
| +int mipi_dbi_command_stackbuf(struct mipi_dbi *mipi, u8 cmd, u8 *data, size_t len); |
| int mipi_dbi_buf_copy(void *dst, struct drm_framebuffer *fb, |
| struct drm_rect *clip, bool swap); |
| /** |
| @@ -99,7 +100,7 @@ int mipi_dbi_buf_copy(void *dst, struct drm_framebuffer *fb, |
| #define mipi_dbi_command(mipi, cmd, seq...) \ |
| ({ \ |
| u8 d[] = { seq }; \ |
| - mipi_dbi_command_buf(mipi, cmd, d, ARRAY_SIZE(d)); \ |
| + mipi_dbi_command_stackbuf(mipi, cmd, d, ARRAY_SIZE(d)); \ |
| }) |
| |
| #ifdef CONFIG_DEBUG_FS |
| -- |
| 2.20.1 |
| |