summaryrefslogtreecommitdiff
path: root/arch/arm/mach-u8500
AgeCommit message (Collapse)Author
2020-01-22board: Add new Samsung "stemmy" board based on ST-Ericsson U8500Stephan Gerhold
The ST-Ericsson U8500 SoC has been used in mass-production for some Android smartphones released around 2012. In particular, Samsung has released more than 5 different smartphones based on U8500, e.g. - Samsung Galaxy S III mini (GT-I8190) "golden" - Samsung Galaxy S Advance (GT-I9070) "janice" - Samsung Galaxy Xcover 2 (GT-S7710) "skomer" and a few others. Mainline Linux has great support for the Ux500 SoC, so these smartphones can also run Linux mainline quite well. Unfortunately, the original Samsung bootloader used on these devices has limitations that prevent booting Linux mainline directly. It keeps the L2 cache enabled, which causes Linux to crash very early, shortly after decompressing the kernel. Using U-Boot allows to circumvent these limitations. We can let the Samsung bootloader chain-load U-Boot and U-Boot locks the L2 cache before booting into Linux. U-Boot has several other advantages - it supports device-trees directly and we are no longer limited to flashing Android boot images through Samsung's proprietary download mode. The Samsung "stemmy" board covers all Samsung devices based on U8500. Add minimal support for "stemmy". For now only UART is supported but this will be extended later. Signed-off-by: Stephan Gerhold <stephan@gerhold.net> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2020-01-22arm: Add support for ST-Ericsson U8500 SoCStephan Gerhold
The NovaThor U8500 SoC was released by ST-Ericsson in 2011. It was used for some development boards like the CALAO Systems Snowball SBC, but mass production was primarily for Android smartphones like the Samsung Galaxy S III mini. Previous support for U8500 was removed in commit 68282f55b846 ("arm: Remove unused ST-Ericsson u8500 arch") since none of the boards were converted to generic boards before the deadline. The new code does not have much in common with the previous code. I have completely rewritten everything, embracing the Driver Model and device trees wherever possible. The U8500 support is a bit more minimal for now - my primary use case is to use U-Boot as alternative bootloader for some of the U8500 Samsung smartphones. At the moment U-Boot is chain-loaded from the original Samsung bootloader. A side effect of this is that we can (temporarily) get away without implementing some functionality - e.g. all clocks are already enabled by the original bootloader. More functionality will be added in future patches. Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: John Rigby <john.rigby@linaro.org> Signed-off-by: Stephan Gerhold <stephan@gerhold.net> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>