Den 04.03.2019 16.10, skrev Andy Shevchenko: > On Mon, Mar 04, 2019 at 03:45:56PM +0100, Noralf Trønnes wrote: >> >> >> Den 22.02.2019 16.58, skrev Andy Shevchenko: >>> On Fri, Feb 22, 2019 at 01:43:29PM +0100, Noralf Trønnes wrote: >>>> 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] >>>> >>> >>> After few runs I don't see the warning anymore. So, >>> Tested-by: Andy Shevchenko <andriy.shevche...@linux.intel.com> >>> >> >> Can I have an ack as well if you're satisfied with it? > > Sure. > > Acked-by: Andy Shevchenko <andriy.shevche...@linux.intel.com> > > I hope to see this in v5.1-rc1.
The patch doesn't apply cleanly on (to be) 5.1 due to this one: drm/tinydrm: Use struct drm_rect https://cgit.freedesktop.org/drm/drm/commit/?id=b051b3459bbae907ef068bcd8b62f73f09ea5016 If it's just a debug warning but no ill effects, it'll show up in 5.2. Otherwise I will have to backport it. Noralf. >> >> Noralf. >> >>> Though I would like to give few more days to monitor the state. >>> (I believe it's fixed) >>> >>>> Reported-by: Andy Shevchenko <andriy.shevche...@linux.intel.com> >>>> Signed-off-by: Noralf Trønnes <nor...@tronnes.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 3f59cfbd31ba..a87078667e04 100644 >>>> --- a/drivers/gpu/drm/tinydrm/ili9225.c >>>> +++ b/drivers/gpu/drm/tinydrm/ili9225.c >>>> @@ -299,7 +299,7 @@ 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; >>>> @@ -309,11 +309,11 @@ 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 246e708a9ff7..4a4cd7e72938 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 >>>> @@ -772,18 +798,18 @@ 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; >>>> >>>> @@ -792,7 +818,7 @@ 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; >>>> @@ -801,7 +827,7 @@ 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, >>>> @@ -819,8 +845,8 @@ 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; >>>> >>>> @@ -850,7 +876,7 @@ 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); >>>> @@ -858,7 +884,7 @@ 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; >>>> @@ -866,18 +892,18 @@ 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 ad7e6bedab5f..464a47d1013d 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; >>>> @@ -83,6 +83,7 @@ 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); >>>> /** >>>> @@ -100,7 +101,7 @@ 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 >>>> >>> > _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
