riscv: thead: Rename T-Head PBMT to MAE

T-Head's vendor extension to set page attributes has the name
MAE (memory attribute extension).
Let's rename it, so it is clear what this referes to.

Link: https://github.com/T-head-Semi/thead-extension-spec/blob/master/xtheadmae.adocReviewed-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Christoph Müllner <christoph.muellner@vrull.eu>
Link: https://lore.kernel.org/r/20240407213236.2121592-2-christoph.muellner@vrull.euSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>

arch/riscv/Kconfig.errata

@@ -82,14 +82,14 @@ config ERRATA_THEAD
 
 	  Otherwise, please say "N" here to avoid unnecessary overhead.
 
-config ERRATA_THEAD_PBMT
-	bool "Apply T-Head memory type errata"
+config ERRATA_THEAD_MAE
+	bool "Apply T-Head's memory attribute extension (XTheadMae) errata"
 	depends on ERRATA_THEAD && 64BIT && MMU
 	select RISCV_ALTERNATIVE_EARLY
 	default y
 	help
-	  This will apply the memory type errata to handle the non-standard
-	  memory type bits in page-table-entries on T-Head SoCs.
+	  This will apply the memory attribute extension errata to handle the
+	  non-standard PTE utilization on T-Head SoCs (XTheadMae).
 
 	  If you don't know what to do here, say "Y".
 

arch/riscv/errata/thead/errata.c

@@ -19,10 +19,10 @@
 #include <asm/patch.h>
 #include <asm/vendorid_list.h>
 
-static bool errata_probe_pbmt(unsigned int stage,
-			      unsigned long arch_id, unsigned long impid)
+static bool errata_probe_mae(unsigned int stage,
+			     unsigned long arch_id, unsigned long impid)
 {
-	if (!IS_ENABLED(CONFIG_ERRATA_THEAD_PBMT))
+	if (!IS_ENABLED(CONFIG_ERRATA_THEAD_MAE))
 		return false;
 
 	if (arch_id != 0 || impid != 0)
@@ -140,8 +140,8 @@ static u32 thead_errata_probe(unsigned int stage,
 {
 	u32 cpu_req_errata = 0;
 
-	if (errata_probe_pbmt(stage, archid, impid))
-		cpu_req_errata |= BIT(ERRATA_THEAD_PBMT);
+	if (errata_probe_mae(stage, archid, impid))
+		cpu_req_errata |= BIT(ERRATA_THEAD_MAE);
 
 	errata_probe_cmo(stage, archid, impid);
 

arch/riscv/include/asm/errata_list.h

@@ -23,7 +23,7 @@
 #endif
 
 #ifdef CONFIG_ERRATA_THEAD
-#define	ERRATA_THEAD_PBMT 0
+#define	ERRATA_THEAD_MAE 0
 #define	ERRATA_THEAD_PMU 1
 #define	ERRATA_THEAD_NUMBER 2
 #endif
@@ -53,20 +53,20 @@ asm(ALTERNATIVE("sfence.vma %0", "sfence.vma", SIFIVE_VENDOR_ID,	\
  * in the default case.
  */
 #define ALT_SVPBMT_SHIFT 61
-#define ALT_THEAD_PBMT_SHIFT 59
+#define ALT_THEAD_MAE_SHIFT 59
 #define ALT_SVPBMT(_val, prot)						\
 asm(ALTERNATIVE_2("li %0, 0\t\nnop",					\
 		  "li %0, %1\t\nslli %0,%0,%3", 0,			\
 			RISCV_ISA_EXT_SVPBMT, CONFIG_RISCV_ISA_SVPBMT,	\
 		  "li %0, %2\t\nslli %0,%0,%4", THEAD_VENDOR_ID,	\
-			ERRATA_THEAD_PBMT, CONFIG_ERRATA_THEAD_PBMT)	\
+			ERRATA_THEAD_MAE, CONFIG_ERRATA_THEAD_MAE)	\
 		: "=r"(_val)						\
 		: "I"(prot##_SVPBMT >> ALT_SVPBMT_SHIFT),		\
-		  "I"(prot##_THEAD >> ALT_THEAD_PBMT_SHIFT),		\
+		  "I"(prot##_THEAD >> ALT_THEAD_MAE_SHIFT),		\
 		  "I"(ALT_SVPBMT_SHIFT),				\
-		  "I"(ALT_THEAD_PBMT_SHIFT))
+		  "I"(ALT_THEAD_MAE_SHIFT))
 
-#ifdef CONFIG_ERRATA_THEAD_PBMT
+#ifdef CONFIG_ERRATA_THEAD_MAE
 /*
  * IO/NOCACHE memory types are handled together with svpbmt,
  * so on T-Head chips, check if no other memory type is set,
@@ -83,11 +83,11 @@ asm volatile(ALTERNATIVE(						\
 	"slli    t3, t3, %3\n\t"					\
 	"or      %0, %0, t3\n\t"					\
 	"2:",  THEAD_VENDOR_ID,						\
-		ERRATA_THEAD_PBMT, CONFIG_ERRATA_THEAD_PBMT)		\
+		ERRATA_THEAD_MAE, CONFIG_ERRATA_THEAD_MAE)		\
 	: "+r"(_val)							\
-	: "I"(_PAGE_MTMASK_THEAD >> ALT_THEAD_PBMT_SHIFT),		\
-	  "I"(_PAGE_PMA_THEAD >> ALT_THEAD_PBMT_SHIFT),			\
-	  "I"(ALT_THEAD_PBMT_SHIFT)					\
+	: "I"(_PAGE_MTMASK_THEAD >> ALT_THEAD_MAE_SHIFT),		\
+	  "I"(_PAGE_PMA_THEAD >> ALT_THEAD_MAE_SHIFT),			\
+	  "I"(ALT_THEAD_MAE_SHIFT)					\
 	: "t3")
 #else
 #define ALT_THEAD_PMA(_val)