Re: [LSF/MM TOPIC NOTES] x86 ZONE_DMA love

From: Geert Uytterhoeven
Date: Thu May 03 2018 - 04:21:04 EST


Hi Luis,

On Thu, Apr 26, 2018 at 11:54 PM, Luis R. Rodriguez <mcgrof@xxxxxxxxxx> wrote:
> x86 implicit and explicit ZONE_DMA users
> -----------------------------------------
>
> We list below all x86 implicit and explicit ZONE_DMA users.
>
> # Explicit x86 users of GFP_DMA or __GFP_DMA
>
> * drivers/iio/common/ssp_sensors - wonder if enabling this on x86 was a mistake.
> Note that this needs SPI and SPI needs HAS_IOMEM. I only see HAS_IOMEM on
> s390 ? But I do think the Intel Minnowboard has SPI, but doubt it has
> the ssp sensor stuff.
>
> * drivers/input/rmi4/rmi_spi.c - same SPI question
> * drivers/media/common/siano/ - make allyesconfig yields it enabled, but
> not sure if this should ever be on x86
> * drivers/media/platform/sti/bdisp/ - likewise
> * drivers/media/platform/sti/hva/ - likewise
> * drivers/media/usb/gspca/ - likewise
> * drivers/mmc/host/wbsd.c - likewise
> * drivers/mtd/nand/gpmi-nand/ - likewise
> * drivers/net/can/spi/hi311x.c - likewise
> * drivers/net/can/spi/mcp251x.c - likewise
> * drivers/net/ethernet/agere/ - likewise
> * drivers/net/ethernet/neterion/vxge/ - likewise
> * drivers/net/ethernet/rocker/ - likewise
> * drivers/net/usb/kalmia.c - likewise
> * drivers/net/ethernet/neterion/vxge/ - likewise
> * drivers/spi/spi-pic32-sqi.c - likewise
> * drivers/spi/spi-sh-msiof.c - likewise

depends on ARCH_SHMOBILE || ARCH_RENESAS || COMPILE_TEST

> * drivers/spi/spi-ti-qspi.c - likewise

I haven't checked the others, but probably you want to disable COMPILE_TEST
to make more educated guesses about driver usage on x86.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds