Hi Ahmad, just a small copied'n'pasted typo: On Tue, Jan 03 2023 at 22:54 +0100, Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx> wrote: > The barebox i.MX images have a preamble that pads the i.MX header to the > offset expected by the BootROM. This allows writing barebox images > directly to offset 0 on SD-Cards and eMMC user area. For some i.MX8M, > these images can't be directly written to eMMC boot partitions and > instead require special handling. Add a note about this to the > documentation. > > Signed-off-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx> > --- > Documentation/boards/imx/nxp-imx8mm-evk.rst | 18 ++++++++++++++++ > Documentation/boards/imx/nxp-imx8mn-evk.rst | 24 +++++++++++++++++++++ > Documentation/boards/imx/nxp-imx8mp-evk.rst | 24 +++++++++++++++++++++ > 3 files changed, 66 insertions(+) > > diff --git a/Documentation/boards/imx/nxp-imx8mm-evk.rst b/Documentation/boards/imx/nxp-imx8mm-evk.rst > index c3cd35ae38a2..7ed7459c08a6 100644 > --- a/Documentation/boards/imx/nxp-imx8mm-evk.rst > +++ b/Documentation/boards/imx/nxp-imx8mm-evk.rst > @@ -69,3 +69,21 @@ board for serial download mode as printed on the PCB. You can start barebox with > the imx-usb-loader tool that comes with barebox like this: > > ./scripts/imx/imx-usb-loader images/barebox-nxp-imx8mm-evk.img > + > +Installing barebox > +================== > + > +When the EVK is strapped to boot from eMMC, the i.MX8M bootrom will > +consult the eMMC ext_csd register to determine whether to boot > +from the active eMMC boot partition or from the user area. > + > +The same barebox image written to the start of the SD-Card can > +be written to the start of the eMMC user area. Power-fail installation > +to the eMMC boot partition requires special handling: > + > + - The barebox image must be written to the inactive boot partition, > + then afterwards, the newly written boot partition is activated > + (This is controlled by the barebox ``mmcX.boot`` variable). > + > +The ``barebox_update`` command takes care of this and need just be > +supplied a barebox image as argument. > diff --git a/Documentation/boards/imx/nxp-imx8mn-evk.rst b/Documentation/boards/imx/nxp-imx8mn-evk.rst > index b920e22d33e9..4c07b949dafb 100644 > --- a/Documentation/boards/imx/nxp-imx8mn-evk.rst > +++ b/Documentation/boards/imx/nxp-imx8mn-evk.rst > @@ -58,3 +58,27 @@ Build barebox > > make imx_v8_defconfig > make > + > +Installing barebox > +================== > + > +When the EVK is strapped to boot from eMMC, the i.MX8M bootrom will > +consult the eMMC ext_csd register to determine whether to boot > +from the active eMMC boot partition or from the user area. > + > +The same barebox image written to the start of the SD-Card can > +be written to the start of the eMMC user area. Power-fail installation > +to the eMMC boot partition requires special handling: > + > + - The barebox image must be written to the inactive boot partition, > + then afterwards, the newly written boot partition is activated > + (This is controlled by the barebox ``mmcX.boot`` variable). > + > + - The barebox image includes a 32KiB preamble that allows the image > + to be directly writable to the start of the SD-Card or eMMC user area. > + Unlike older i.MX8M, the i.MX8MN BootROM expects the bootloader to not > + start as an offset when booting from eMMC boot partitions, thus the first s/start as an offset/start at an offset/ > + 32KiB must be stripped. > + > +The ``barebox_update`` command takes care of this and need just be > +supplied a barebox image as argument. > diff --git a/Documentation/boards/imx/nxp-imx8mp-evk.rst b/Documentation/boards/imx/nxp-imx8mp-evk.rst > index 1074992f2f88..60e9f9eaea5d 100644 > --- a/Documentation/boards/imx/nxp-imx8mp-evk.rst > +++ b/Documentation/boards/imx/nxp-imx8mp-evk.rst > @@ -66,3 +66,27 @@ Boot Configuration > The NXP i.MX8MP-EVK board has four switches responsible for configuring > bootsource/boot mode. The settings for the different boot sources are > printed on the board. > + > +Installing barebox > +================== > + > +When the EVK is strapped to boot from eMMC, the i.MX8M bootrom will > +consult the eMMC ext_csd register to determine whether to boot > +from the active eMMC boot partition or from the user area. > + > +The same barebox image written to the start of the SD-Card can > +be written to the start of the eMMC user area. Power-fail installation > +to the eMMC boot partition requires special handling: > + > + - The barebox image must be written to the inactive boot partition, > + then afterwards, the newly written boot partition is activated > + (This is controlled by the barebox ``mmcX.boot`` variable). > + > + - The barebox image includes a 32KiB preamble that allows the image > + to be directly writable to the start of the SD-Card or eMMC user area. > + Unlike older i.MX8M, the i.MX8MP BootROM expects the bootloader to not > + start as an offset when booting from eMMC boot partitions, thus the first s/start as an offset/start at an offset/ Best regards Ulrich > + 32KiB must be stripped. > + > +The ``barebox_update`` command takes care of this and need just be > +supplied a barebox image as argument. -- Pengutronix e.K. | Ulrich Ölmann | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
