Re: [PATCH] drivers: uio: new driver uio_fsl_85xx_cache_sram

From: Scott Wood
Date: Fri Apr 17 2020 - 19:02:21 EST


On Fri, 2020-04-17 at 10:21 -0700, Wang Wenhu wrote:
> Implements a new uio driver for freescale 85xx platforms to access
> the Cache-Sram form user level. It is extremely helpful for the user
> space applications that require high performance memory accesses.
>
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Cc: Christophe Leroy <christophe.leroy@xxxxxx>
> Cc: Scott Wood <oss@xxxxxxxxxxxx>
> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
> Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
> Signed-off-by: Wang Wenhu <wenhu.wang@xxxxxxxx>
> ---
> drivers/uio/Kconfig | 8 +
> drivers/uio/Makefile | 1 +
> drivers/uio/uio_fsl_85xx_cache_sram.c | 407 ++++++++++++++++++++++++++
> 3 files changed, 416 insertions(+)
> create mode 100644 drivers/uio/uio_fsl_85xx_cache_sram.c

NACK, we don't need two copies of this code in the kernel. Please just wait a
bit and I'll send a patch to have the existing driver expose a dynamic
allocation interface to userspace.

-Scott