3 files changed, 91 insertions, 9 deletions

diff --git a/arch/arm64/mm/cache.S b/arch/arm64/mm/cache.S
index 83c27b6e6dca..7f1dbe962cf5 100644
--- a/arch/arm64/mm/cache.S
+++ b/arch/arm64/mm/cache.S
@@ -109,20 +109,25 @@ ENTRY(__clean_dcache_area_pou)
 ENDPROC(__clean_dcache_area_pou)
 
 /*
- *	__dma_inv_area(start, size)
- *	- start   - virtual start address of region
+ *	__inval_dcache_area(kaddr, size)
+ *
+ * 	Ensure that any D-cache lines for the interval [kaddr, kaddr+size)
+ * 	are invalidated. Any partial lines at the ends of the interval are
+ *	also cleaned to PoC to prevent data loss.
+ *
+ *	- kaddr   - kernel address
  *	- size    - size in question
  */
-__dma_inv_area:
-	add	x1, x1, x0
+ENTRY(__inval_dcache_area)
 	/* FALLTHROUGH */
 
 /*
- *	__inval_cache_range(start, end)
- *	- start   - start address of region
- *	- end     - end address of region
+ *	__dma_inv_area(start, size)
+ *	- start   - virtual start address of region
+ *	- size    - size in question
  */
-ENTRY(__inval_cache_range)
+__dma_inv_area:
+	add	x1, x1, x0
 	dcache_line_size x2, x3
 	sub	x3, x2, #1
 	tst	x1, x3				// end cache line aligned?
@@ -140,7 +145,7 @@ ENTRY(__inval_cache_range)
 	b.lo	2b
 	dsb	sy
 	ret
-ENDPIPROC(__inval_cache_range)
+ENDPIPROC(__inval_dcache_area)
 ENDPROC(__dma_inv_area)
 
 /*
@@ -167,6 +172,20 @@ ENDPIPROC(__clean_dcache_area_poc)
 ENDPROC(__dma_clean_area)
 
 /*
+ *	__clean_dcache_area_pop(kaddr, size)
+ *
+ * 	Ensure that any D-cache lines for the interval [kaddr, kaddr+size)
+ * 	are cleaned to the PoP.
+ *
+ *	- kaddr   - kernel address
+ *	- size    - size in question
+ */
+ENTRY(__clean_dcache_area_pop)
+	dcache_by_line_op cvap, sy, x0, x1, x2, x3
+	ret
+ENDPIPROC(__clean_dcache_area_pop)
+
+/*
  *	__dma_flush_area(start, size)
  *
  *	clean & invalidate D / U line
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 2509e4fe6992..52ee273afeec 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -82,6 +82,49 @@ static inline int notify_page_fault(struct pt_regs *regs, unsigned int esr)
 }
 #endif
 
+static void data_abort_decode(unsigned int esr)
+{
+	pr_alert("Data abort info:\n");
+
+	if (esr & ESR_ELx_ISV) {
+		pr_alert("  Access size = %u byte(s)\n",
+			 1U << ((esr & ESR_ELx_SAS) >> ESR_ELx_SAS_SHIFT));
+		pr_alert("  SSE = %lu, SRT = %lu\n",
+			 (esr & ESR_ELx_SSE) >> ESR_ELx_SSE_SHIFT,
+			 (esr & ESR_ELx_SRT_MASK) >> ESR_ELx_SRT_SHIFT);
+		pr_alert("  SF = %lu, AR = %lu\n",
+			 (esr & ESR_ELx_SF) >> ESR_ELx_SF_SHIFT,
+			 (esr & ESR_ELx_AR) >> ESR_ELx_AR_SHIFT);
+	} else {
+		pr_alert("  ISV = 0, ISS = 0x%08lu\n", esr & ESR_ELx_ISS_MASK);
+	}
+
+	pr_alert("  CM = %lu, WnR = %lu\n",
+		 (esr & ESR_ELx_CM) >> ESR_ELx_CM_SHIFT,
+		 (esr & ESR_ELx_WNR) >> ESR_ELx_WNR_SHIFT);
+}
+
+/*
+ * Decode mem abort information
+ */
+static void mem_abort_decode(unsigned int esr)
+{
+	pr_alert("Mem abort info:\n");
+
+	pr_alert("  Exception class = %s, IL = %u bits\n",
+		 esr_get_class_string(esr),
+		 (esr & ESR_ELx_IL) ? 32 : 16);
+	pr_alert("  SET = %lu, FnV = %lu\n",
+		 (esr & ESR_ELx_SET_MASK) >> ESR_ELx_SET_SHIFT,
+		 (esr & ESR_ELx_FnV) >> ESR_ELx_FnV_SHIFT);
+	pr_alert("  EA = %lu, S1PTW = %lu\n",
+		 (esr & ESR_ELx_EA) >> ESR_ELx_EA_SHIFT,
+		 (esr & ESR_ELx_S1PTW) >> ESR_ELx_S1PTW_SHIFT);
+
+	if (esr_is_data_abort(esr))
+		data_abort_decode(esr);
+}
+
 /*
  * Dump out the page tables associated with 'addr' in the currently active mm.
  */
@@ -248,6 +291,8 @@ static void __do_kernel_fault(unsigned long addr, unsigned int esr,
 	pr_alert("Unable to handle kernel %s at virtual address %08lx\n", msg,
 		 addr);
 
+	mem_abort_decode(esr);
+
 	show_pte(addr);
 	die("Oops", regs, esr);
 	bust_spinlocks(0);
@@ -702,6 +747,8 @@ asmlinkage void __exception do_mem_abort(unsigned long addr, unsigned int esr,
 	pr_alert("Unhandled fault: %s (0x%08x) at 0x%016lx\n",
 		 inf->name, esr, addr);
 
+	mem_abort_decode(esr);
+
 	info.si_signo = inf->sig;
 	info.si_errno = 0;
 	info.si_code  = inf->code;
diff --git a/arch/arm64/mm/flush.c b/arch/arm64/mm/flush.c
index 21a8d828cbf4..e36ed5087b5c 100644
--- a/arch/arm64/mm/flush.c
+++ b/arch/arm64/mm/flush.c
@@ -83,3 +83,19 @@ EXPORT_SYMBOL(flush_dcache_page);
  * Additional functions defined in assembly.
  */
 EXPORT_SYMBOL(flush_icache_range);
+
+#ifdef CONFIG_ARCH_HAS_PMEM_API
+void arch_wb_cache_pmem(void *addr, size_t size)
+{
+	/* Ensure order against any prior non-cacheable writes */
+	dmb(osh);
+	__clean_dcache_area_pop(addr, size);
+}
+EXPORT_SYMBOL_GPL(arch_wb_cache_pmem);
+
+void arch_invalidate_pmem(void *addr, size_t size)
+{
+	__inval_dcache_area(addr, size);
+}
+EXPORT_SYMBOL_GPL(arch_invalidate_pmem);
+#endif