As the boot order in the kernel continues to change, sometimes it may
happen that the eSDHC controller mmc@2150000 (the one for eMMC) gets
probed before the one at mmc@2140000 (for external SD cards). The effect
is that the eMMC controller gets the /dev/mmcblk0 name, and the SD card
gets /dev/mmcblk1.
Since the introduction of this SoC, that has never happened in practice,
even though it was never guaranteed in theory. Setting
"root=/dev/mmcblk0p2" in /proc/cmdline has always caused the kernel to
use the second partition from the SD card as the rootfs.
The NXP development boards are typically shipped with either
- LSDK, which uses "root=UUID=", or
- OpenIL, which uses "root=/dev/mmcblkNp2"
So for OpenIL, let's preserve that old behavior by adding some aliases
which create naming consistency (for LSDK it doesn't matter):
- the SD card controller uses /dev/mmcblk0
- the eMMC controller uses /dev/mmcblk1
For the Kontron SL28 boards, Michael Walle says that they are shipped
with "root=UUID=" already, so the probing order doesn't matter, but it
is more natural to him for /dev/mmcblk0 to be the eMMC, so let's do it
the other way around there.
The aliases are parsed by mmc_alloc_host() in drivers/mmc/core/host.c.
Cc: Ashish Kumar <[email protected]>
Cc: Yangbo Lu <[email protected]>
Cc: Michael Walle <[email protected]>
Signed-off-by: Vladimir Oltean <[email protected]>
---
arch/arm64/boot/dts/freescale/fsl-ls1028a-kontron-sl28.dts | 2 ++
arch/arm64/boot/dts/freescale/fsl-ls1028a-qds.dts | 2 ++
arch/arm64/boot/dts/freescale/fsl-ls1028a-rdb.dts | 2 ++
3 files changed, 6 insertions(+)
diff --git a/arch/arm64/boot/dts/freescale/fsl-ls1028a-kontron-sl28.dts b/arch/arm64/boot/dts/freescale/fsl-ls1028a-kontron-sl28.dts
index 8161dd237971..99a17c187aa8 100644
--- a/arch/arm64/boot/dts/freescale/fsl-ls1028a-kontron-sl28.dts
+++ b/arch/arm64/boot/dts/freescale/fsl-ls1028a-kontron-sl28.dts
@@ -23,6 +23,8 @@ aliases {
serial2 = &lpuart1;
spi0 = &fspi;
spi1 = &dspi2;
+ mmc0 = &esdhc1;
+ mmc1 = &esdhc;
};
buttons0 {
diff --git a/arch/arm64/boot/dts/freescale/fsl-ls1028a-qds.dts b/arch/arm64/boot/dts/freescale/fsl-ls1028a-qds.dts
index 13cdc958ba3e..c0786b713791 100644
--- a/arch/arm64/boot/dts/freescale/fsl-ls1028a-qds.dts
+++ b/arch/arm64/boot/dts/freescale/fsl-ls1028a-qds.dts
@@ -23,6 +23,8 @@ aliases {
gpio2 = &gpio3;
serial0 = &duart0;
serial1 = &duart1;
+ mmc0 = &esdhc;
+ mmc1 = &esdhc1;
};
chosen {
diff --git a/arch/arm64/boot/dts/freescale/fsl-ls1028a-rdb.dts b/arch/arm64/boot/dts/freescale/fsl-ls1028a-rdb.dts
index 1efb61cff454..c1d1ba459307 100644
--- a/arch/arm64/boot/dts/freescale/fsl-ls1028a-rdb.dts
+++ b/arch/arm64/boot/dts/freescale/fsl-ls1028a-rdb.dts
@@ -19,6 +19,8 @@ aliases {
crypto = &crypto;
serial0 = &duart0;
serial1 = &duart1;
+ mmc0 = &esdhc;
+ mmc1 = &esdhc1;
};
chosen {
--
2.25.1
Am 2020-11-19 17:38, schrieb Vladimir Oltean:
> As the boot order in the kernel continues to change, sometimes it may
> happen that the eSDHC controller mmc@2150000 (the one for eMMC) gets
> probed before the one at mmc@2140000 (for external SD cards). The
> effect
> is that the eMMC controller gets the /dev/mmcblk0 name, and the SD card
> gets /dev/mmcblk1.
>
> Since the introduction of this SoC, that has never happened in
> practice,
> even though it was never guaranteed in theory. Setting
> "root=/dev/mmcblk0p2" in /proc/cmdline has always caused the kernel to
> use the second partition from the SD card as the rootfs.
>
> The NXP development boards are typically shipped with either
> - LSDK, which uses "root=UUID=", or
> - OpenIL, which uses "root=/dev/mmcblkNp2"
>
> So for OpenIL, let's preserve that old behavior by adding some aliases
> which create naming consistency (for LSDK it doesn't matter):
> - the SD card controller uses /dev/mmcblk0
> - the eMMC controller uses /dev/mmcblk1
>
> For the Kontron SL28 boards, Michael Walle says that they are shipped
> with "root=UUID=" already, so the probing order doesn't matter, but it
> is more natural to him for /dev/mmcblk0 to be the eMMC, so let's do it
> the other way around there.
>
> The aliases are parsed by mmc_alloc_host() in drivers/mmc/core/host.c.
>
> Cc: Ashish Kumar <[email protected]>
> Cc: Yangbo Lu <[email protected]>
> Cc: Michael Walle <[email protected]>
> Signed-off-by: Vladimir Oltean <[email protected]>
Acked-by: Michael Walle <[email protected]> [for the sl28 boards]
-michael
On Thu, Nov 19, 2020 at 06:38:21PM +0200, Vladimir Oltean wrote:
> As the boot order in the kernel continues to change, sometimes it may
> happen that the eSDHC controller mmc@2150000 (the one for eMMC) gets
> probed before the one at mmc@2140000 (for external SD cards). The effect
> is that the eMMC controller gets the /dev/mmcblk0 name, and the SD card
> gets /dev/mmcblk1.
>
> Since the introduction of this SoC, that has never happened in practice,
> even though it was never guaranteed in theory. Setting
> "root=/dev/mmcblk0p2" in /proc/cmdline has always caused the kernel to
> use the second partition from the SD card as the rootfs.
>
> The NXP development boards are typically shipped with either
> - LSDK, which uses "root=UUID=", or
> - OpenIL, which uses "root=/dev/mmcblkNp2"
>
> So for OpenIL, let's preserve that old behavior by adding some aliases
> which create naming consistency (for LSDK it doesn't matter):
> - the SD card controller uses /dev/mmcblk0
> - the eMMC controller uses /dev/mmcblk1
>
> For the Kontron SL28 boards, Michael Walle says that they are shipped
> with "root=UUID=" already, so the probing order doesn't matter, but it
> is more natural to him for /dev/mmcblk0 to be the eMMC, so let's do it
> the other way around there.
>
> The aliases are parsed by mmc_alloc_host() in drivers/mmc/core/host.c.
>
> Cc: Ashish Kumar <[email protected]>
> Cc: Yangbo Lu <[email protected]>
> Cc: Michael Walle <[email protected]>
> Signed-off-by: Vladimir Oltean <[email protected]>
Applied, thanks.