riscv: support for Svpbmt and D1 memory types

Adds support for Svpbmt, the "Supervisor-mode: page-based memory types"
extension, which allows pages to be marked as non-cacheable and/or I/O.
This also includes support for the Allwinner D1's page table attributes
via the alternatives framework, which differ from Svpbmt in various ways
but are necessary to make the D1 function.

* palmer/riscv-d1:
  riscv: add memory-type errata for T-Head
  riscv: don't use global static vars to store alternative data
  riscv: remove FIXMAP_PAGE_IO and fall back to its default value
  riscv: add RISC-V Svpbmt extension support
  riscv: Fix accessing pfn bits in PTEs for non-32bit variants
  riscv: move boot alternatives to after fill_hwcap
  riscv: prevent compressed instructions in alternatives
  riscv: extend concatenated alternatives-lines to the same length
  riscv: implement ALTERNATIVE_2 macro
  riscv: implement module alternatives
  riscv: allow different stages with alternatives
  riscv: integrate alternatives better into the main architecture

1 files changed, 0 insertions, 10 deletions

diff --git a/arch/riscv/include/asm/pgtable-bits.h b/arch/riscv/include/asm/pgtable-bits.h
index a6b0c89824c2..b9e13a8fe2b7 100644
--- a/arch/riscv/include/asm/pgtable-bits.h
+++ b/arch/riscv/include/asm/pgtable-bits.h
@@ -6,12 +6,6 @@
 #ifndef _ASM_RISCV_PGTABLE_BITS_H
 #define _ASM_RISCV_PGTABLE_BITS_H
 
-/*
- * PTE format:
- * | XLEN-1  10 | 9             8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0
- *       PFN      reserved for SW   D   A   G   U   X   W   R   V
- */
-
 #define _PAGE_ACCESSED_OFFSET 6
 
 #define _PAGE_PRESENT   (1 << 0)
@@ -35,10 +29,6 @@
 
 #define _PAGE_PFN_SHIFT 10
 
-/* Set of bits to preserve across pte_modify() */
-#define _PAGE_CHG_MASK  (~(unsigned long)(_PAGE_PRESENT | _PAGE_READ |	\
-					  _PAGE_WRITE | _PAGE_EXEC |	\
-					  _PAGE_USER | _PAGE_GLOBAL))
 /*
  * when all of R/W/X are zero, the PTE is a pointer to the next level
  * of the page table; otherwise, it is a leaf PTE.