Merge tag 'arm64-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64

Pull arm64 patches from Catalin Marinas:

 - SMP support for the PSCI booting protocol (power state coordination
   interface).

 - Simple earlyprintk support.

 - Platform devices populated by default from the DT (SoC-agnostic).

 - CONTEXTIDR support (used by external trace tools).

* tag 'arm64-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64:
  arm64: mm: update CONTEXTIDR register to contain PID of current process
  arm64: atomics: fix grossly inconsistent asm constraints for exclusives
  arm64: compat: use compat_uptr_t type for compat_ucontext.uc_link
  arm64: Select ARCH_WANT_FRAME_POINTERS
  arm64: Add kvm_para.h and xor.h generic headers
  arm64: SMP: enable PSCI boot method
  arm64: psci: add support for PSCI invocations from the kernel
  arm64: SMP: rework the SMP code to be enabling method agnostic
  arm64: perf: add guest vs host discrimination
  arm64: add COMPAT_PSR_*_BIT flags
  arm64: Add simple earlyprintk support
  arm64: Populate the platform devices

1 files changed, 10 insertions, 2 deletions

diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index 368ad1f7c36c..0a0a49756826 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -82,10 +82,8 @@
 
 #ifdef CONFIG_ARM64_64K_PAGES
 #define MM_MMUFLAGS     PTE_ATTRINDX(MT_NORMAL) | PTE_FLAGS
-#define IO_MMUFLAGS     PTE_ATTRINDX(MT_DEVICE_nGnRE) | PTE_XN | PTE_FLAGS
 #else
 #define MM_MMUFLAGS     PMD_ATTRINDX(MT_NORMAL) | PMD_FLAGS
-#define IO_MMUFLAGS     PMD_ATTRINDX(MT_DEVICE_nGnRE) | PMD_SECT_XN | PMD_FLAGS
 #endif
 
 /*
@@ -368,6 +366,7 @@ ENDPROC(__calc_phys_offset)
  *   - identity mapping to enable the MMU (low address, TTBR0)
  *   - first few MB of the kernel linear mapping to jump to once the MMU has
  *     been enabled, including the FDT blob (TTBR1)
+ *   - UART mapping if CONFIG_EARLY_PRINTK is enabled (TTBR1)
  */
 __create_page_tables:
         pgtbl   x25, x26, x24                   // idmap_pg_dir and swapper_pg_dir addresses
@@ -420,6 +419,15 @@ __create_page_tables:
         sub     x6, x6, #1                      // inclusive range
         create_block_map x0, x7, x3, x5, x6
 1:
+#ifdef CONFIG_EARLY_PRINTK
+        /*
+         * Create the pgd entry for the UART mapping. The full mapping is done
+         * later based earlyprintk kernel parameter.
+         */
+        ldr     x5, =EARLYCON_IOBASE            // UART virtual address
+        add     x0, x26, #2 * PAGE_SIZE         // section table address
+        create_pgd_entry x26, x0, x5, x6, x7
+#endif
         ret
 ENDPROC(__create_page_tables)
         .ltorg