device: sama7d65: Fix initial clock for can devices

Add CAN clock ids and modify initial clock for
CAN devices in hw_postinit, preventing failed
CAN initialisation modules in Linux.

Signed-off-by: Romain Sioen <[email protected]>
Signed-off-by: Hari Prasath Gujulan Elango <[email protected]>

Author: Romain Sioen

device/sama7d65/sama7d65.c

@@ -1103,5 +1103,26 @@ void hw_postinit(void)
 	pmc_mck_cfg_set(0, mck0_prescaler,
 			AT91C_PMC_PRES | AT91C_PMC_MDIV | AT91C_PMC_CSS);
 #endif
+
+	/*
+	 * Change CAN GCLK source clock from SLW_CLK to MAIN_CLK
+	 * because of timout issue at CAN initialisation in Linux.
+	 * This allows CAN devices to be ready earlier in boot process.
+	 */
+	pmc_enable_generic_clock(AT91C_ID_MCAN0,
+				 GCK_CSS_MAIN_CLK,
+				 2);
+	pmc_enable_generic_clock(AT91C_ID_MCAN1,
+				 GCK_CSS_MAIN_CLK,
+				 2);
+	pmc_enable_generic_clock(AT91C_ID_MCAN2,
+				 GCK_CSS_MAIN_CLK,
+				 2);
+	pmc_enable_generic_clock(AT91C_ID_MCAN3,
+				 GCK_CSS_MAIN_CLK,
+				 2);
+	pmc_enable_generic_clock(AT91C_ID_MCAN4,
+				 GCK_CSS_MAIN_CLK,
+				 2);
 }
 

include/arch/sama7d65.h

@@ -35,6 +35,12 @@
 #define AT91C_ID_FLEXCOM9	43
 #define AT91C_ID_FLEXCOM10	44
 
+#define AT91C_ID_MCAN0      58
+#define AT91C_ID_MCAN1      59
+#define AT91C_ID_MCAN2      60
+#define AT91C_ID_MCAN3      61
+#define AT91C_ID_MCAN4      62
+
 #define AT91C_ID_QSPI0		73
 #define AT91C_ID_QSPI1		74
 #define AT91C_ID_SDMMC0		75