Linus Walleij 8a996b2d8a ARM: dts: ux500: Reserve memory carveouts ... The Ux500 platforms have some memory carveouts set aside for communicating with the modem and for the initial secure software (ISSW). These areas are protected by the memory controller and will result in an external abort if accessed like common read/write memory. On the legacy boot loaders, these were set aside by using cmdline arguments such as this: mem=96M@0 mem_mtrace=15M@96M mem_mshared=1M@111M mem_modem=16M@112M mali.mali_mem=32M@128M mem=96M@160M hwmem=127M@256M mem_issw=1M@383M mem_ram_console=1M@384M mem=638M@385M Reserve the relevant areas in the device tree instead. The "mali", "hwmem", "mem_ram_console" and the trailing 1MB at the end of the memory reservations in the list are not relevant for the upstream kernel as these are nowadays replaced with upstream technologies such as CMA. The modem and ISSW reservations are necessary. This was manifested in a bug that surfaced in response to commit 7fef431be9 ("mm/page_alloc: place pages to tail in __free_pages_core()") which changes the behaviour of memory allocations in such a way that the platform will sooner run into these dangerous areas, with "Unhandled fault: imprecise external abort (0xc06) at 0xb6fd83dc" or similar: the real reason turns out to be that the PTE is pointing right into one of the reserved memory areas. We were just lucky until now. We need to augment the DB8500 and DB8520 SoCs similarly and also create a new include for the DB9500 used in the Snowball since this does not have a modem and thus does not need the modem memory reservation, albeit it needs the ISSW reservation. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Cc: stable@vger.kernel.org Cc: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201213225517.3838501-1-linus.walleij@linaro.org' Signed-off-by: Arnd Bergmann <arnd@arndb.de>		2021-01-15 17:59:31 +01:00
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bootp
compressed	ARM updates for 5.11:	2020-12-22 13:34:27 -08:00
dts	ARM: dts: ux500: Reserve memory carveouts	2021-01-15 17:59:31 +01:00
.gitignore
deflate_xip_data.sh
install.sh
Makefile