How about moving those sysctls under a dev.sdhci.X.slotY.debug parent node? This way we can add more debug tunables in the future.

Changes:

• provide a sanity check for isc_dma_width,
• introduce a DMA_WIDTH_TO_BUS_LOWADDR macro to correctly handle edge cases where isc_dma_width equals either 0 or the number of bits in BUS_SPACE_MAXADDR

Reconsider turning the devmethod into an admin completion queue specific handler, which both reduces the scope of the call and makes the usecase more obvious.

@mmel @manu @mw Any remarks to this patch and the related ones in stack?

Change qoriq_make_gpio_res return type to bool.

In D26153#583899, @manu wrote:

In D26153#583898, @ar_semihalf.com wrote:

In D26153#583890, @kibab wrote:

Regarding the partitions: it would be interesting to see the output of ls /dev/sdda* on MMCCAM kernel, probably the partitions got detected but not printed on boot.

With GENERIC-MMCCAM, my kernel failed to mount a rootfs located on an unrelated usb drive (perhaps this hints towards a bigger issue?), so I wasn't able to properly inspect the mmc partitions from userspace. I did however list all available drives via mountroot and there were no partitions listed for sdda0.

That's really weird ...
Is there any shared clocks/regulator between mmc and usb that could explain usb not being available if mmc isn't probed/init correctly ?

Not to my knowledge. sdhci_fsl_fdt doesn't modify the parent clock in any way and the prescalers/dividers it sets are internal to this IP block.

In D26153#583890, @kibab wrote:

Regarding the partitions: it would be interesting to see the output of ls /dev/sdda* on MMCCAM kernel, probably the partitions got detected but not printed on boot.

With GENERIC-MMCCAM, my kernel failed to mount a rootfs located on an unrelated usb drive (perhaps this hints towards a bigger issue?), so I wasn't able to properly inspect the mmc partitions from userspace. I did however list all available drives via mountroot and there were no partitions listed for sdda0.

changes:

• drop "All rights reserved",
• bump copyright to 2020,
• add SPDX identifier,
• integrate @mmel's changes for LX2160A compat. string

In D26153#583257, @manu wrote:

Sorry I forgot about it, I'll review this later today.
Two quick question :

• could you drop the all right reserved ?

Sure.

• Was it tested with an MMCCAM kernel ? I'd like us to switch to it for 13.

I just tested this driver with MMCCAM on hardware that contains a single eMMC chip. On the old mmc stack this card (correctly) displays the following partitions:

mmcsd0
mmcsd0boot0
mmcsd0boot1
mmcsd0p1
mmcsd0p2
mmcsd0p3
mmcsd0p4
mmcsd0rpmb

however, with MMCCAM I only get sdda0 and no partitions:

sdda0 at sdhci_slot0 bus 0 scbus0 target 0 lun 0
sdda0: Relative addr: 00000002
Card features: <MMC Memory High-Capacity>
Card memory OCR: 00ff8080
sdda0: Serial Number C565B3C
sdda0: MMCHC 008G30 0.4 SN C565B3CD MFG 03/2002 by 17 0x0000

I reckon this is not an expected behavior with eMMC and I'm not missing any extra hooks for this stack in my driver?

@manu @mmel @mw Any remarks to this patch?