platform/sam3u: initial eefc

Signed-off-by: Rafael Silva <perigoso@riseup.net>

Author: perigoso

config/families/sam3u.toml

@@ -29,6 +29,7 @@ ld_flags = [
 ]
 source = [
 	'startup.c',
+	'eefc.c',
 	'wdt.c',
 ]
 

src/platform/sam3u/eefc.c

@@ -0,0 +1,31 @@
+/*
+ * SPDX-License-Identifier: MIT
+ * SPDX-FileCopyrightText: 2021 Rafael Silva <perigoso@riseup.net>
+ */
+
+#include <sam.h>
+
+#include "platform/sam3u/eefc.h"
+
+void eefc_config_waitstates(const u32 frequency)
+{
+	if (frequency <= 27000000UL)
+		EFC0->EEFC_FMR = (EFC0->EEFC_FMR & ~EEFC_FMR_FWS_Msk) | (0 << EEFC_FMR_FWS_Pos);
+	else if (frequency <= 47000000UL)
+		EFC0->EEFC_FMR = (EFC0->EEFC_FMR & ~EEFC_FMR_FWS_Msk) | (1 << EEFC_FMR_FWS_Pos);
+	else if (frequency <= 84000000UL)
+		EFC0->EEFC_FMR = (EFC0->EEFC_FMR & ~EEFC_FMR_FWS_Msk) | (2 << EEFC_FMR_FWS_Pos);
+	else
+		EFC0->EEFC_FMR = (EFC0->EEFC_FMR & ~EEFC_FMR_FWS_Msk) | (3 << EEFC_FMR_FWS_Pos);
+
+#ifdef _SAM3U_EFC1_INSTANCE_
+	if (frequency <= 27000000UL)
+		EFC1->EEFC_FMR = (EFC0->EEFC_FMR & ~EEFC_FMR_FWS_Msk) | (0 << EEFC_FMR_FWS_Pos);
+	else if (frequency <= 47000000UL)
+		EFC1->EEFC_FMR = (EFC0->EEFC_FMR & ~EEFC_FMR_FWS_Msk) | (1 << EEFC_FMR_FWS_Pos);
+	else if (frequency <= 84000000UL)
+		EFC1->EEFC_FMR = (EFC0->EEFC_FMR & ~EEFC_FMR_FWS_Msk) | (2 << EEFC_FMR_FWS_Pos);
+	else
+		EFC1->EEFC_FMR = (EFC0->EEFC_FMR & ~EEFC_FMR_FWS_Msk) | (3 << EEFC_FMR_FWS_Pos);
+#endif /* _SAM3U_EFC1_INSTANCE_ */
+}

src/platform/sam3u/eefc.h

@@ -0,0 +1,12 @@
+/*
+ * SPDX-License-Identifier: MIT
+ * SPDX-FileCopyrightText: 2021 Rafael Silva <perigoso@riseup.net>
+ */
+
+#pragma once
+
+#include <sam.h>
+
+#include "util/types.h"
+
+void eefc_config_waitstates(const u32 frequency);