MLK-16266-01 ARM: imx: improve the soc revision calculation flow

On our i.MX6 SOC, the DIGPROG register is used for represent the
SOC ID and silicon revision. The revision has two part: MAJOR and
MINOR. each is represented in 8 bits in the register.

  bits [15:8]: reflect the MAJOR part of the revision;
  bits [7:0]: reflect the MINOR part of the revision;

In our linux kernel, the soc revision is represented in 8 bits. MAJOR
part and MINOR each occupy 4 bits.

previous method does NOT take care about the MAJOR part in DIGPROG register.
So reformat the revision read from the HW to compatible the revision format
used in kernel.

Signed-off-by: Bai Ping <ping.bai@nxp.com>
(cherry picked from commit cf6fa1477149d4bddd096c71b46fa6c4cf9cf750)
Acked-by: Stefan Agner <stefan.agner@toradex.com>

1 files changed, 19 insertions, 33 deletions

diff --git a/arch/arm/mach-imx/anatop.c b/arch/arm/mach-imx/anatop.c
index 77b2326a3a61..2470e1a4fead 100644
--- a/arch/arm/mach-imx/anatop.c
+++ b/arch/arm/mach-imx/anatop.c
@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2013-2016 Freescale Semiconductor, Inc.
+ * Copyright 2017 NXP.
  *
  * The code contained herein is licensed under the GNU General Public
  * License. You may obtain a copy of the GNU General Public License
@@ -209,6 +210,7 @@ void __init imx_init_revision_from_anatop(void)
 	unsigned int revision;
 	u32 digprog;
 	u16 offset = ANADIG_DIGPROG;
+	u16 major_part, minor_part;
 
 	np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-anatop");
 	anatop_base = of_iomap(np, 0);
@@ -220,41 +222,25 @@ void __init imx_init_revision_from_anatop(void)
 	digprog = readl_relaxed(anatop_base + offset);
 	iounmap(anatop_base);
 
-	switch (digprog & 0xff) {
-	case 0:
-		if (digprog >> 8 & 0x01)
-			revision = IMX_CHIP_REVISION_2_0;
-		else
-			revision = IMX_CHIP_REVISION_1_0;
-		break;
-	case 1:
-		revision = IMX_CHIP_REVISION_1_1;
-		break;
-	case 2:
-		revision = IMX_CHIP_REVISION_1_2;
-		break;
-	case 3:
-		revision = IMX_CHIP_REVISION_1_3;
-		break;
-	case 4:
-		revision = IMX_CHIP_REVISION_1_4;
-		break;
-	case 5:
-		/*
-		 * i.MX6DQ TO1.5 is defined as Rev 1.3 in Data Sheet, marked
-		 * as 'D' in Part Number last character.
-		 */
-		revision = IMX_CHIP_REVISION_1_5;
-		break;
-	default:
+	/*
+	 * On i.MX7D digprog value match linux version format, so
+	 * it needn't map again and we can use register value directly.
+	 */
+	if (of_device_is_compatible(np, "fsl,imx7d-anatop")) {
+		revision = digprog & 0xff;
+	} else {
 		/*
-		 * Fail back to return raw register value instead of 0xff.
-		 * It will be easy know version information in SOC if it
-		 * can't recongized by known version. And some chip like
-		 * i.MX7D soc digprog value match linux version format,
-		 * needn't map again and direct use register value.
+		 * MAJOR: [15:8], the major silicon revison;
+		 * MINOR: [7: 0], the minor silicon revison;
+		 *
+		 * please refer to the i.MX RM for the detailed
+		 * silicon revison bit define.
+		 * format the major part and minor part to match the
+		 * linux kernel soc version format.
 		 */
-		revision = digprog & 0xff;
+		major_part = (digprog >> 8) & 0xf;
+		minor_part = digprog & 0xf;
+		revision = ((major_part + 1) << 4) | minor_part;
 	}
 
 	mxc_set_cpu_type(digprog >> 16 & 0xff);