[RFC] arm64: early_ioremap fails to map ACPI MADT on 64K pages

[Yu Peng]

Hi Lorenzo, Hanjun, Will,

Thanks for confirming.

I will send a proper patch for this. The change I plan to post is along
these lines:

diff --git a/arch/arm64/include/asm/fixmap.h b/arch/arm64/include/asm/fixmap.h
index ... .. ...
--- a/arch/arm64/include/asm/fixmap.h
+++ b/arch/arm64/include/asm/fixmap.h
@@ -79,7 +79,11 @@ enum fixed_addresses {
 	 * Temporary boot-time mappings, used by early_ioremap(),
 	 * before ioremap() is functional.
 	 */
+#ifdef CONFIG_ARM64_64K_PAGES
+#define NR_FIX_BTMAPS		(SZ_512K / PAGE_SIZE)
+#else
 #define NR_FIX_BTMAPS		(SZ_256K / PAGE_SIZE)
+#endif
 #define FIX_BTMAPS_SLOTS	7
 #define TOTAL_FIX_BTMAPS	(NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS)

Thanks,
Yu Peng