Merge pull request #1274 from dp-arm/dp/a75

AMU fixes for Cortex-A75

1 files changed, 70 insertions, 0 deletions

diff --git a/lib/cpus/aarch64/cpuamu.c b/lib/cpus/aarch64/cpuamu.c
new file mode 100644
index 000000000..b9bad8604
--- /dev/null
+++ b/lib/cpus/aarch64/cpuamu.c
@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <cpuamu.h>
+#include <platform.h>
+#include <pubsub_events.h>
+
+#define CPUAMU_NR_COUNTERS	5U
+
+struct amu_ctx {
+	uint64_t cnts[CPUAMU_NR_COUNTERS];
+	unsigned int mask;
+};
+
+static struct amu_ctx amu_ctxs[PLATFORM_CORE_COUNT];
+
+int midr_match(unsigned int cpu_midr)
+{
+	unsigned int midr, midr_mask;
+
+	midr = (unsigned int)read_midr();
+	midr_mask = (MIDR_IMPL_MASK << MIDR_IMPL_SHIFT) |
+		(MIDR_PN_MASK << MIDR_PN_SHIFT);
+	return ((midr & midr_mask) == (cpu_midr & midr_mask));
+}
+
+void cpuamu_context_save(unsigned int nr_counters)
+{
+	struct amu_ctx *ctx = &amu_ctxs[plat_my_core_pos()];
+	unsigned int i;
+
+	assert(nr_counters <= CPUAMU_NR_COUNTERS);
+
+	/* Save counter configuration */
+	ctx->mask = cpuamu_read_cpuamcntenset_el0();
+
+	/* Disable counters */
+	cpuamu_write_cpuamcntenclr_el0(ctx->mask);
+	isb();
+
+	/* Save counters */
+	for (i = 0; i < nr_counters; i++)
+		ctx->cnts[i] = cpuamu_cnt_read(i);
+}
+
+void cpuamu_context_restore(unsigned int nr_counters)
+{
+	struct amu_ctx *ctx = &amu_ctxs[plat_my_core_pos()];
+	unsigned int i;
+
+	assert(nr_counters <= CPUAMU_NR_COUNTERS);
+
+	/*
+	 * Disable counters.  They were enabled early in the
+	 * CPU reset function.
+	 */
+	cpuamu_write_cpuamcntenclr_el0(ctx->mask);
+	isb();
+
+	/* Restore counters */
+	for (i = 0; i < nr_counters; i++)
+		cpuamu_cnt_write(i, ctx->cnts[i]);
+	isb();
+
+	/* Restore counter configuration */
+	cpuamu_write_cpuamcntenset_el0(ctx->mask);
+}