Re: [PATCH v3 0/4] ARM: i.MX8: add DDRC-ECC support

[Sascha Hauer <s.hauer@pengutronix.de>]

Hi Steffen,

This doesn't apply cleanly. Could you rebase on master?

Sascha

On Wed, Mar 11, 2026 at 09:38:13AM +0100, Steffen Trumtrar wrote:
> The i.MX8 DDRC controller supports using inline ECC with the DDR RAM.
> Inline ECC reduces the usable RAM size by 1/8: 7/8 RAM is for data and
> 1/8 RAM is for the ECC bits. Also, measuring random memory writes in
> linux with
> 
>     stress-ng --memthrash 4 --memthrash-method chunk1 -t 1m --metrics
> 
> shows a performance decrease by ~10%.
> 
> If a board wants to support ECC, the lpddr4 RAM settings in the
> according lpddr4-timing-* must be adapted to enable and configure the
> ECC registers.
> 
> Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
> ---
> Changes in v3:
> - move timing struct to own noinline function
> - rename dram_timing_info->size -> dram_timing_info->ecc_full_size
> - replace #ifdef with IS_ENABLED
> - add defines for ECC_STRIDE/INLINE/SCRUB_SIZE
> - remove imx8mq-ddrc, only quad x plus has ecc
> - Fix kconfig text
> - Link to v2: https://lore.barebox.org/20260309-v2026-02-0-topic-imx8-ecc-v2-0-6aab6d795061@pengutronix.de
> 
> Changes in v2:
> - prt8ml: move ram timings to header
> - prt8ml: build two images: with and without ecc
> - add RAM size and scrubbing function to generic code
> - Link to v1: https://lore.barebox.org/20260304-v2026-02-0-topic-imx8-ecc-v1-0-700698530c5c@pengutronix.de
> 
> ---
> David Jander (3):
>       arm: mach-imx: esdctl.c: Add support for imx8mp inline ECC
>       drivers: ddr: imx8m: ddr_init.c: support ECC scrubbing
>       arm: boards: protonic-imx8ml: Add ECC + scrubbing
> 
> Steffen Trumtrar (1):
>       ARM: i.MX: esdctl: fix spelling of ad(d)ress
> 
>  arch/arm/boards/protonic-imx8m/Makefile            |    2 +-
>  arch/arm/boards/protonic-imx8m/lowlevel-prt8ml.c   |   29 +-
>  .../protonic-imx8m/lpddr4-timing-prt8ml-ecc.c      |   26 +
>  .../boards/protonic-imx8m/lpddr4-timing-prt8ml.c   | 1100 +------------------
>  .../boards/protonic-imx8m/lpddr4-timing-prt8ml.h   | 1123 ++++++++++++++++++++
>  arch/arm/dts/imx8mp-prt8ml.dts                     |   10 +-
>  arch/arm/mach-imx/Kconfig                          |   11 +
>  arch/arm/mach-imx/esdctl.c                         |   86 +-
>  drivers/ddr/imx/imx8m_ddr_init.c                   |   96 ++
>  images/Makefile.imx                                |    2 +
>  include/soc/imx/ddr.h                              |    1 +
>  include/soc/imx8m/ddr.h                            |    2 +
>  12 files changed, 1376 insertions(+), 1112 deletions(-)
> ---
> base-commit: f4122cb473bf8ca2d3d84cf7cd3c981d1da3309f
> change-id: 20260304-v2026-02-0-topic-imx8-ecc-9206fee1f037
> 
> Best regards,
> -- 
> Steffen Trumtrar <s.trumtrar@pengutronix.de>
> 
> 

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