mx25: Clean up lowlevel_init

Clean up mx25 lowlevel_init:
 - Add comments.
 - Do not use write32 repeatedly with the same value in order not to increase
   code size.
 - Make register values configurable.
 - Use macro parameters with default values instead of literal constants.
 - Use defined macros instead of duplicating code.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Cc: Stefano Babic <sbabic@denx.de>
Cc: John Rigby <jcrigby@gmail.com>
Cc: Matthias Weisser <weisserm@arcor.de>

2 files changed, 68 insertions, 53 deletions

diff --git a/arch/arm/include/asm/arch-mx25/macro.h b/arch/arm/include/asm/arch-mx25/macro.h
index 3b694da..56cae36 100644
--- a/arch/arm/include/asm/arch-mx25/macro.h
+++ b/arch/arm/include/asm/arch-mx25/macro.h
@@ -32,32 +32,75 @@
 
 #include <asm/arch/imx-regs.h>
 #include <generated/asm-offsets.h>
+#include <asm/macro.h>
 
-.macro init_aips
-	write32	IMX_AIPS1_BASE + AIPS_MPR_0_7, 0x77777777
-	write32	IMX_AIPS1_BASE + AIPS_MPR_8_15, 0x77777777
-	write32	IMX_AIPS2_BASE + AIPS_MPR_0_7, 0x77777777
-	write32	IMX_AIPS2_BASE + AIPS_MPR_8_15, 0x77777777
+/*
+ * AIPS setup - Only setup MPROTx registers.
+ * The PACR default values are good.
+ *
+ * Default argument values:
+ *  - MPR: Set all MPROTx to be non-bufferable, trusted for R/W, not forced to
+ *    user-mode.
+ */
+.macro init_aips mpr=0x77777777
+	ldr	r0, =IMX_AIPS1_BASE
+	ldr	r1, =\mpr
+	str	r1, [r0, #AIPS_MPR_0_7]
+	str	r1, [r0, #AIPS_MPR_8_15]
+	ldr	r2, =IMX_AIPS2_BASE
+	str	r1, [r2, #AIPS_MPR_0_7]
+	str	r1, [r2, #AIPS_MPR_8_15]
 .endm
 
-.macro init_max
-	write32	IMX_MAX_BASE + MAX_MPR0, 0x43210
-	write32	IMX_MAX_BASE + MAX_MPR1, 0x43210
-	write32	IMX_MAX_BASE + MAX_MPR2, 0x43210
-	write32	IMX_MAX_BASE + MAX_MPR3, 0x43210
-	write32	IMX_MAX_BASE + MAX_MPR4, 0x43210
-
-	write32	IMX_MAX_BASE + MAX_SGPCR0, 0x10
-	write32	IMX_MAX_BASE + MAX_SGPCR1, 0x10
-	write32	IMX_MAX_BASE + MAX_SGPCR2, 0x10
-	write32	IMX_MAX_BASE + MAX_SGPCR3, 0x10
-	write32	IMX_MAX_BASE + MAX_SGPCR4, 0x10
+/*
+ * MAX (Multi-Layer AHB Crossbar Switch) setup
+ *
+ * Default argument values:
+ *  - MPR: priority is IAHB > DAHB > USBOTG > RTIC > eSDHC2/SDMA
+ *  - SGPCR: always park on last master
+ *  - MGPCR: restore default values
+ */
+.macro init_max mpr=0x00043210, sgpcr=0x00000010, mgpcr=0x00000000
+	ldr	r0, =IMX_MAX_BASE
+	ldr	r1, =\mpr
+	str	r1, [r0, #MAX_MPR0]	/* for S0 */
+	str	r1, [r0, #MAX_MPR1]	/* for S1 */
+	str	r1, [r0, #MAX_MPR2]	/* for S2 */
+	str	r1, [r0, #MAX_MPR3]	/* for S3 */
+	str	r1, [r0, #MAX_MPR4]	/* for S4 */
+	ldr	r1, =\sgpcr
+	str	r1, [r0, #MAX_SGPCR0]	/* for S0 */
+	str	r1, [r0, #MAX_SGPCR1]	/* for S1 */
+	str	r1, [r0, #MAX_SGPCR2]	/* for S2 */
+	str	r1, [r0, #MAX_SGPCR3]	/* for S3 */
+	str	r1, [r0, #MAX_SGPCR4]	/* for S4 */
+	ldr	r1, =\mgpcr
+	str	r1, [r0, #MAX_MGPCR0]	/* for M0 */
+	str	r1, [r0, #MAX_MGPCR1]	/* for M1 */
+	str	r1, [r0, #MAX_MGPCR2]	/* for M2 */
+	str	r1, [r0, #MAX_MGPCR3]	/* for M3 */
+	str	r1, [r0, #MAX_MGPCR4]	/* for M4 */
+.endm
 
-	write32	IMX_MAX_BASE + MAX_MGPCR0, 0x0
-	write32	IMX_MAX_BASE + MAX_MGPCR1, 0x0
-	write32	IMX_MAX_BASE + MAX_MGPCR2, 0x0
-	write32	IMX_MAX_BASE + MAX_MGPCR3, 0x0
-	write32	IMX_MAX_BASE + MAX_MGPCR4, 0x0
+/*
+ * M3IF setup
+ *
+ * Default argument values:
+ *  - CTL:
+ * MRRP[0] = LCDC on priority list (1 << 0)			= 0x00000001
+ * MRRP[1] = MAX1 not on priority list (0 << 1)			= 0x00000000
+ * MRRP[2] = MAX0 not on priority list (0 << 2)			= 0x00000000
+ * MRRP[3] = USBH not on priority list (0 << 3)			= 0x00000000
+ * MRRP[4] = SDMA not on priority list (0 << 4)			= 0x00000000
+ * MRRP[5] = eSDHC1/ATA/FEC not on priority list (0 << 5)	= 0x00000000
+ * MRRP[6] = LCDC/SLCDC/MAX2 not on priority list (0 << 6)	= 0x00000000
+ * MRRP[7] = CSI not on priority list (0 << 7)			= 0x00000000
+ *								------------
+ *								  0x00000001
+ */
+.macro init_m3if ctl=0x00000001
+	/* M3IF Control Register (M3IFCTL) */
+	write32	IMX_M3IF_CTRL_BASE, \ctl
 .endm
 
 #endif /* __ASSEMBLY__ */
diff --git a/board/karo/tx25/lowlevel_init.S b/board/karo/tx25/lowlevel_init.S
index eb3f187..3e46ed9 100644
--- a/board/karo/tx25/lowlevel_init.S
+++ b/board/karo/tx25/lowlevel_init.S
@@ -22,37 +22,7 @@
  */
 
 #include <asm/macro.h>
-
-.macro init_aips
-	write32	0x43f00000, 0x77777777
-	write32	0x43f00004, 0x77777777
-	write32	0x43f00000, 0x77777777
-	write32	0x53f00004, 0x77777777
-.endm
-
-.macro init_max
-	write32	0x43f04000, 0x43210
-	write32	0x43f04100, 0x43210
-	write32	0x43f04200, 0x43210
-	write32	0x43f04300, 0x43210
-	write32	0x43f04400, 0x43210
-
-	write32	0x43f04010, 0x10
-	write32	0x43f04110, 0x10
-	write32	0x43f04210, 0x10
-	write32	0x43f04310, 0x10
-	write32	0x43f04410, 0x10
-
-	write32	0x43f04800, 0x0
-	write32	0x43f04900, 0x0
-	write32	0x43f04a00, 0x0
-	write32	0x43f04b00, 0x0
-	write32	0x43f04c00, 0x0
-.endm
-
-.macro init_m3if
-	write32 0xb8003000, 0x1
-.endm
+#include <asm/arch/macro.h>
 
 .macro init_clocks
 	/*
@@ -64,6 +34,8 @@
 	 * 0x00600000 makes CLKO parent clk the USB clk
 	 */
 	write32	0x53f80064, 0x45600000
+
+	/* CCTL: ARM = 399 MHz, AHB = 133 MHz */
 	write32	0x53f80008, 0x20034000
 
 	/*