can: flexcan: struct flexcan_regs: document registers not affected by soft reset

This patch documents which registers are not affected by a soft reset of the
flexcan IP core.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20200922144429.2613631-5-mkl@pengutronix.de

drivers/net/can/flexcan.c

@@ -203,12 +203,12 @@ struct flexcan_mb {
 /* Structure of the hardware registers */
 struct flexcan_regs {
 	u32 mcr;		/* 0x00 */
-	u32 ctrl;		/* 0x04 */
+	u32 ctrl;		/* 0x04 - Not affected by Soft Reset */
 	u32 timer;		/* 0x08 */
 	u32 tcr;		/* 0x0c */
-	u32 rxgmask;		/* 0x10 */
-	u32 rx14mask;		/* 0x14 */
-	u32 rx15mask;		/* 0x18 */
+	u32 rxgmask;		/* 0x10 - Not affected by Soft Reset */
+	u32 rx14mask;		/* 0x14 - Not affected by Soft Reset */
+	u32 rx15mask;		/* 0x18 - Not affected by Soft Reset */
 	u32 ecr;		/* 0x1c */
 	u32 esr;		/* 0x20 */
 	u32 imask2;		/* 0x24 */
@@ -217,20 +217,20 @@ struct flexcan_regs {
 	u32 iflag1;		/* 0x30 */
 	union {			/* 0x34 */
 		u32 gfwr_mx28;	/* MX28, MX53 */
-		u32 ctrl2;	/* MX6, VF610 */
+		u32 ctrl2;	/* MX6, VF610 - Not affected by Soft Reset */
 	};
 	u32 esr2;		/* 0x38 */
 	u32 imeur;		/* 0x3c */
 	u32 lrfr;		/* 0x40 */
 	u32 crcr;		/* 0x44 */
 	u32 rxfgmask;		/* 0x48 */
-	u32 rxfir;		/* 0x4c */
-	u32 cbt;		/* 0x50 */
+	u32 rxfir;		/* 0x4c - Not affected by Soft Reset */
+	u32 cbt;		/* 0x50 - Not affected by Soft Reset */
 	u32 _reserved2;		/* 0x54 */
 	u32 dbg1;		/* 0x58 */
 	u32 dbg2;		/* 0x5c */
 	u32 _reserved3[8];	/* 0x60 */
-	u8 mb[2][512];		/* 0x80 */
+	u8 mb[2][512];		/* 0x80 - Not affected by Soft Reset */
 	/* FIFO-mode:
 	 *			MB
 	 * 0x080...0x08f	0	RX message buffer
@@ -242,7 +242,7 @@ struct flexcan_regs {
 	 *				(mx6, vf610)
 	 */
 	u32 _reserved4[256];	/* 0x480 */
-	u32 rximr[64];		/* 0x880 */
+	u32 rximr[64];		/* 0x880 - Not affected by Soft Reset */
 	u32 _reserved5[24];	/* 0x980 */
 	u32 gfwr_mx6;		/* 0x9e0 - MX6 */
 	u32 _reserved6[63];	/* 0x9e4 */
@@ -255,8 +255,8 @@ struct flexcan_regs {
 	u32 rerrsynr;		/* 0xaf8 */
 	u32 errsr;		/* 0xafc */
 	u32 _reserved7[64];	/* 0xb00 */
-	u32 fdctrl;		/* 0xc00 */
-	u32 fdcbt;		/* 0xc04 */
+	u32 fdctrl;		/* 0xc00 - Not affected by Soft Reset */
+	u32 fdcbt;		/* 0xc04 - Not affected by Soft Reset */
 	u32 fdcrc;		/* 0xc08 */
 };