From: Rob Herring <[email protected]> If ATAGs or DTB pointer is not within first 1MB of RAM, then the boot params will not be mapped early enough, so map the 1MB region that r2 points to. Only map the first 1MB when r2 is 0.
Some assembly improvements from Nicolas Pitre. Signed-off-by: Rob Herring <[email protected]> --- arch/arm/kernel/head.S | 19 ++++++++++++++++++- 1 files changed, 18 insertions(+), 1 deletions(-) diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S index 65d9489..9c688bf 100644 --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S @@ -205,15 +205,32 @@ __create_page_tables: #endif /* - * Then map first 1MB of ram in case it contains our boot params. + * Then map first 1MB of ram if boot params address is not specified. */ + cmp r2, #0 + bne 1f add r0, r4, #PAGE_OFFSET >> 18 orr r6, r7, #(PHYS_OFFSET & 0xff000000) .if (PHYS_OFFSET & 0x00f00000) orr r6, r6, #(PHYS_OFFSET & 0x00f00000) .endif str r6, [r0] + b 2f + /* + * Otherwise map the 1MB region r2 points to (atags or dtb) + */ +1: mov r0, r2, lsr #20 + mov r0, r0, lsl #20 + sub r3, r0, #(PHYS_OFFSET & 0xff000000) + .if (PHYS_OFFSET & 0x00f00000) + sub r3, r3, #(PHYS_OFFSET & 0x00f00000) + .endif + add r3, r3, #PAGE_OFFSET + add r3, r4, r3, lsr #18 + orr r6, r7, r0 + str r6, [r3] +2: #ifdef CONFIG_DEBUG_LL #ifndef CONFIG_DEBUG_ICEDCC /* -- 1.7.1 _______________________________________________ devicetree-discuss mailing list [email protected] https://lists.ozlabs.org/listinfo/devicetree-discuss
