[PATCH] spi: spi-geni-qcom: enable SPI_CONTROLLER_MUST_TX for GPI DMA mode

[PATCH] spi: spi-geni-qcom: enable SPI_CONTROLLER_MUST_TX for GPI DMA mode

[Dmitry Baryshkov]

The GPI DMA mode requires for TX DMA to be prepared. Force SPI core to
provide TX buffer even if the caller didn't provide one by setting the
SPI_CONTROLLER_MUST_TX flag.

Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
Mem abort info:
  ESR = 0x0000000096000004
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x04: level 0 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000004
  CM = 0, WnR = 0
user pgtable: 4k pages, 48-bit VAs, pgdp=0000000815b82000
[0000000000000010] pgd=0000000000000000, p4d=0000000000000000
Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
Modules linked in:
pstate: 61400005 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
pc : gpi_prep_slave_sg+0x3a4/0x5a8
lr : gpi_prep_slave_sg+0xcc/0x5a8
sp : ffff80000a2c3930
x29: ffff80000a2c3930 x28: ffff80000a2c3c58 x27: ffff4e744d8307f0
x26: 0000000000000001 x25: ffff4e7440f55810 x24: 0000000000000000
x23: 0000000000000001 x22: 0000000000000001 x21: 0000000000000003
x20: ffff4e7440c1f800 x19: ffff4e744d1f8618 x18: ffffd8ac41787e68
x17: 000000040044ffff x16: 005000f2b5503510 x15: 0000000000000100
x14: ffff4e744d608000 x13: 0000000800000002 x12: 0000000600000004
x11: 0000000000000000 x10: fffffffffff9f980 x9 : 0000000000000000
x8 : ffff4e7440c1fa00 x7 : 0000000000000000 x6 : 000000000000003f
x5 : 00000000ffffffff x4 : 0000000000000900 x3 : 0000000000000200
x2 : 0000000100000000 x1 : ffff4e7451f73400 x0 : ffff4e744d1f8610
Call trace:
 gpi_prep_slave_sg+0x3a4/0x5a8
 spi_geni_transfer_one+0x190/0x558
 spi_transfer_one_message+0x424/0x800
 __spi_pump_transfer_message+0x248/0x670
 __spi_sync+0x2cc/0x3a8
 spi_sync+0x3c/0x68
 spidev_sync_read+0xb0/0x108
 spidev_read+0x54/0x110
 vfs_read+0xc8/0x270
 ksys_read+0xec/0x110
 __arm64_sys_read+0x24/0x38
 invoke_syscall+0x50/0x128
 el0_svc_common.constprop.0+0xd4/0x100
 do_el0_svc+0x40/0xa8
 el0_svc+0x34/0x108
 el0t_64_sync_handler+0xf4/0x120
 el0t_64_sync+0x190/0x198
Code: 94079d2b 17ffff94 a90573fb f940a660 (f9400b06)
---[ end trace 0000000000000000 ]---

Fixes: b59c122484ec ("spi: spi-geni-qcom: Add support for GPI dma")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/spi/spi-geni-qcom.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/spi/spi-geni-qcom.c b/drivers/spi/spi-geni-qcom.c
index a98b781b103a..15b39008a554 100644
--- a/drivers/spi/spi-geni-qcom.c
+++ b/drivers/spi/spi-geni-qcom.c
@@ -1098,6 +1098,12 @@ static int spi_geni_probe(struct platform_device *pdev)
 	if (mas->cur_xfer_mode == GENI_SE_FIFO)
 		spi->set_cs = spi_geni_set_cs;
 
+	/*
+	 * TX is required per GSI spec, see setup_gsi_xfer().
+	 */
+	if (mas->cur_xfer_mode == GENI_GPI_DMA)
+		spi->flags = SPI_CONTROLLER_MUST_TX;
+
 	ret = request_irq(mas->irq, geni_spi_isr, 0, dev_name(dev), spi);
 	if (ret)
 		goto spi_geni_release_dma;
-- 
2.40.1

Re: [PATCH] spi: spi-geni-qcom: enable SPI_CONTROLLER_MUST_TX for GPI DMA mode

[Mark Brown]

[-- Attachment #1: Type: text/plain, Size: 863 bytes --]

On Thu, Jun 29, 2023 at 12:58:47PM +0300, Dmitry Baryshkov wrote:
> The GPI DMA mode requires for TX DMA to be prepared. Force SPI core to
> provide TX buffer even if the caller didn't provide one by setting the
> SPI_CONTROLLER_MUST_TX flag.
> 
> Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
> Mem abort info:
>   ESR = 0x0000000096000004
>   EC = 0x25: DABT (current EL), IL = 32 bits
>   SET = 0, FnV = 0
>   EA = 0, S1PTW = 0

Please think hard before including complete backtraces in upstream
reports, they are very large and contain almost no useful information
relative to their size so often obscure the relevant content in your
message. If part of the backtrace is usefully illustrative (it often is
for search engines if nothing else) then it's usually better to pull out
the relevant sections.

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

Re: [PATCH] spi: spi-geni-qcom: enable SPI_CONTROLLER_MUST_TX for GPI DMA mode

[Mark Brown]

On Thu, 29 Jun 2023 12:58:47 +0300, Dmitry Baryshkov wrote:
> The GPI DMA mode requires for TX DMA to be prepared. Force SPI core to
> provide TX buffer even if the caller didn't provide one by setting the
> SPI_CONTROLLER_MUST_TX flag.
> 
> Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
> Mem abort info:
>   ESR = 0x0000000096000004
>   EC = 0x25: DABT (current EL), IL = 32 bits
>   SET = 0, FnV = 0
>   EA = 0, S1PTW = 0
>   FSC = 0x04: level 0 translation fault
> Data abort info:
>   ISV = 0, ISS = 0x00000004
>   CM = 0, WnR = 0
> user pgtable: 4k pages, 48-bit VAs, pgdp=0000000815b82000
> [0000000000000010] pgd=0000000000000000, p4d=0000000000000000
> Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
> Modules linked in:
> pstate: 61400005 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
> pc : gpi_prep_slave_sg+0x3a4/0x5a8
> lr : gpi_prep_slave_sg+0xcc/0x5a8
> sp : ffff80000a2c3930
> x29: ffff80000a2c3930 x28: ffff80000a2c3c58 x27: ffff4e744d8307f0
> x26: 0000000000000001 x25: ffff4e7440f55810 x24: 0000000000000000
> x23: 0000000000000001 x22: 0000000000000001 x21: 0000000000000003
> x20: ffff4e7440c1f800 x19: ffff4e744d1f8618 x18: ffffd8ac41787e68
> x17: 000000040044ffff x16: 005000f2b5503510 x15: 0000000000000100
> x14: ffff4e744d608000 x13: 0000000800000002 x12: 0000000600000004
> x11: 0000000000000000 x10: fffffffffff9f980 x9 : 0000000000000000
> x8 : ffff4e7440c1fa00 x7 : 0000000000000000 x6 : 000000000000003f
> x5 : 00000000ffffffff x4 : 0000000000000900 x3 : 0000000000000200
> x2 : 0000000100000000 x1 : ffff4e7451f73400 x0 : ffff4e744d1f8610
> Call trace:
>  gpi_prep_slave_sg+0x3a4/0x5a8
>  spi_geni_transfer_one+0x190/0x558
>  spi_transfer_one_message+0x424/0x800
>  __spi_pump_transfer_message+0x248/0x670
>  __spi_sync+0x2cc/0x3a8
>  spi_sync+0x3c/0x68
>  spidev_sync_read+0xb0/0x108
>  spidev_read+0x54/0x110
>  vfs_read+0xc8/0x270
>  ksys_read+0xec/0x110
>  __arm64_sys_read+0x24/0x38
>  invoke_syscall+0x50/0x128
>  el0_svc_common.constprop.0+0xd4/0x100
>  do_el0_svc+0x40/0xa8
>  el0_svc+0x34/0x108
>  el0t_64_sync_handler+0xf4/0x120
>  el0t_64_sync+0x190/0x198
> Code: 94079d2b 17ffff94 a90573fb f940a660 (f9400b06)
> ---[ end trace 0000000000000000 ]---
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next

Thanks!

[1/1] spi: spi-geni-qcom: enable SPI_CONTROLLER_MUST_TX for GPI DMA mode
      commit: d10005837be83906bbd2078c3b4f9dfcbd6c95b6

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark