On 14/10/15 22:13, Jeremy Linton wrote:
On 10/14/2015 06:20 AM, Suzuki K. Poulose wrote:
+ * Checks if the selected granule size is supported by the CPU.
+ * If it doesn't park the CPU
The problem is when you park the boot CPU.
I think for EFI there is a slightly better error mechanism. This tweak will
print an
error and return to the EFI boot manager rather than hanging the machine
without any
notification. Now it prints:
EFI stub: Booting Linux Kernel...
EFI stub: ERROR: 16K granule not supported by this machine
EFI stub: ERROR: Failed to relocate kernel
FS4:\>
Nice ! I will pick this up.
Signed-off-by: Jeremy Linton <jeremy.lin...@arm.com>
---
arch/arm64/kernel/efi-stub.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/arch/arm64/kernel/efi-stub.c b/arch/arm64/kernel/efi-stub.c
index 816120e..90fb868 100644
--- a/arch/arm64/kernel/efi-stub.c
+++ b/arch/arm64/kernel/efi-stub.c
@@ -25,6 +25,20 @@ efi_status_t __init handle_kernel_image(efi_system_table_t
*sys_table_arg,
unsigned long kernel_size, kernel_memsize = 0;
unsigned long nr_pages;
void *old_image_addr = (void *)*image_addr;
+ u32 aa64mmfr0_el1;
+
+#ifdef CONFIG_ARM64_16K_PAGES
I would prefer to have it on for all page sizes and not just 16K, to be on a
safer side
+ /*
+ * check to see if this kernel image is
+ * compatible with the current system
+ */
+ asm volatile("mrs %0, ID_AA64MMFR0_EL1" : "=r" (aa64mmfr0_el1));
+ aa64mmfr0_el1 >>= ID_AA64MMFR0_TGRAN16_SHIFT;
+ if ((aa64mmfr0_el1 & ID_AA64MMFR0_TGRAN4_ON) == 0) {
+ pr_efi_err(sys_table_arg, "16K granule not supported by this
machine\n");
+ return EFI_UNSUPPORTED;
+ }
+#endif
Thanks
Suzuki
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