| Message ID | 20190222124329.23046-1-noralf@tronnes.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | tinydrm/mipi-dbi: Use dma-safe buffers for all SPI transfers | expand |
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.shevchenko@linux.intel.com> Though I would like to give few more days to monitor the state. (I believe it's fixed) > Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > Signed-off-by: Noralf Trønnes <noralf@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 >
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.shevchenko@linux.intel.com> > Can I have an ack as well if you're satisfied with it? Noralf. > Though I would like to give few more days to monitor the state. > (I believe it's fixed) > >> Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> >> Signed-off-by: Noralf Trønnes <noralf@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 >> >
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.shevchenko@linux.intel.com> > > > > Can I have an ack as well if you're satisfied with it? Sure. Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> I hope to see this in v5.1-rc1. > > Noralf. > > > Though I would like to give few more days to monitor the state. > > (I believe it's fixed) > > > >> Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > >> Signed-off-by: Noralf Trønnes <noralf@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 > >> > >
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.shevchenko@linux.intel.com> >>> >> >> Can I have an ack as well if you're satisfied with it? > > Sure. > > Acked-by: Andy Shevchenko <andriy.shevchenko@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.shevchenko@linux.intel.com> >>>> Signed-off-by: Noralf Trønnes <noralf@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 >>>> >>> >
On Mon, Mar 04, 2019 at 06:51:33PM +0100, Noralf Trønnes wrote: > 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: > > Acked-by: Andy Shevchenko <andriy.shevchenko@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. For x86 it's just a debug message, since on x86 stack memory is DMA capable. But in general this should be fixed for any possible scenarios.
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
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 Trønnes <noralf@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(-)