armv7: import updated cache/MMU stuff from coreboot

This imports the cache/MMU code from coreboot as of 1877cee.

Change-Id: I97ec8b9640921a94a4b27d89e4ae6185e9f96f18
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Reviewed-by: Gabe Black <gabeblack@google.com>
Reviewed-on: https://gerrit.chromium.org/gerrit/48288
Commit-Queue: Stefan Reinauer <reinauer@google.com>
Tested-by: Stefan Reinauer <reinauer@google.com>
Reviewed-on: http://review.coreboot.org/4134
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

payloads/libpayload/arch/armv7/cache.c

@@ -31,7 +31,7 @@
  * Reference: ARM Architecture Reference Manual, ARMv7-A and ARMv7-R edition
  */
 
-#include <inttypes.h>
+#include <stdint.h>
 
 #include <arch/cache.h>
 
@@ -149,14 +149,39 @@ static void dcache_op_set_way(enum dcache_op op)
 	isb();
 }
 
+static void dcache_foreach(enum dcache_op op)
+{
+	uint32_t clidr;
+	int level;
+
+	clidr = read_clidr();
+	for (level = 0; level < 7; level++) {
+		unsigned int ctype = (clidr >> (level * 3)) & 0x7;
+		uint32_t csselr;
+
+		switch(ctype) {
+		case 0x2:
+		case 0x3:
+		case 0x4:
+			csselr = level << 1;
+			write_csselr(csselr);
+			dcache_op_set_way(op);
+			break;
+		default:
+			/* no cache, icache only, or reserved */
+			break;
+		}
+	}
+}
+
 void dcache_clean_invalidate_all(void)
 {
-	dcache_op_set_way(OP_DCCISW);
+	dcache_foreach(OP_DCCISW);
 }
 
 void dcache_invalidate_all(void)
 {
-	dcache_op_set_way(OP_DCISW);
+	dcache_foreach(OP_DCISW);
 }
 
 static unsigned int line_bytes(void)
@@ -212,15 +237,9 @@ void dcache_clean_invalidate_by_mva(unsigned long addr, unsigned long len)
 
 void dcache_mmu_disable(void)
 {
-	uint32_t sctlr, csselr;
+	uint32_t sctlr;
-
-	/* ensure L1 data/unified cache is selected */
-	csselr = read_csselr();
-	csselr &= ~0xf;
-	write_csselr(csselr);
 
 	dcache_clean_invalidate_all();
-
 	sctlr = read_sctlr();
 	sctlr &= ~(SCTLR_C | SCTLR_M);
 	write_sctlr(sctlr);
@@ -264,6 +283,8 @@ void armv7_invalidate_caches(void)
 		case 0x2:
 		case 0x4:
 			/* dcache only or unified cache */
+			csselr = level << 1;
+			write_csselr(csselr);
 			dcache_invalidate_all();
 			break;
 		case 0x3:
@@ -272,7 +293,7 @@ void armv7_invalidate_caches(void)
 			write_csselr(csselr);
 			icache_invalidate_all();
 
-			csselr = level < 1;
+			csselr = level << 1;
 			write_csselr(csselr);
 			dcache_invalidate_all();
 			break;

payloads/libpayload/include/armv7/arch/cache.h

@@ -219,10 +219,29 @@ static inline void write_csselr(uint32_t val)
 	isb();	/* ISB to sync the change to CCSIDR */
 }
 
-/* read system control register (SCTLR) */
+/* read L2 control register (L2CTLR) */
-static inline unsigned int read_sctlr(void)
+static inline uint32_t read_l2ctlr(void)
 {
-	unsigned int val;
+	uint32_t val = 0;
+	asm volatile ("mrc p15, 1, %0, c9, c0, 2" : "=r" (val));
+	return val;
+}
+
+/* write L2 control register (L2CTLR) */
+static inline void write_l2ctlr(uint32_t val)
+{
+	/*
+	 * Note: L2CTLR can only be written when the L2 memory system
+	 * is idle, ie before the MMU is enabled.
+	 */
+	asm volatile("mcr p15, 1, %0, c9, c0, 2" : : "r" (val) : "memory" );
+	isb();
+}
+
+/* read system control register (SCTLR) */
+static inline uint32_t read_sctlr(void)
+{
+	uint32_t val;
 	asm volatile ("mrc p15, 0, %0, c1, c0, 0" : "=r" (val));
 	return val;
 }