cpu/allwinner/a10: Refactor API for gating clocks to peripherals

Rather than having to track which bit in which register should be
cleared or set to gate or ungate the clock to a certain peripheral,
provide a simplified enum which encodes the register and bit. This
change comes with a function which decodes the enum and gates/ungates
the clock.

This also removes the register-dependent bitmasks for APB0 and APB1
gating registers.

Change-Id: Ib3ca16e54eb37eadc3ceb88f4ccc497829ac34bc
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Reviewed-on: http://review.coreboot.org/4571
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

src/cpu/allwinner/a10/Makefile.inc

@@ -1,3 +1,4 @@
+bootblock-y	+= clock.c
 bootblock-y	+= pinmux.c
 bootblock-y	+= bootblock_media.c
 bootblock-$(CONFIG_BOOTBLOCK_CONSOLE) += uart.c

src/cpu/allwinner/a10/clock.c

@@ -0,0 +1,42 @@
+/*
+ * Helpers for clock control and gating on Allwinner CPUs
+ *
+ * Copyright (C) 2013  Alexandru Gagniuc <mr.nuke.me@gmail.com>
+ * Subject to the GNU GPL v2, or (at your option) any later version.
+ */
+
+#include "clock.h"
+
+#include <arch/io.h>
+
+/**
+ * \brief Enable the clock source for the peripheral
+ *
+ * @param[in] periph peripheral and clock type to enable @see a1x_clken
+ */
+void a1x_periph_clock_enable(enum a1x_clken periph)
+{
+	void *addr;
+	u32 reg32;
+
+	addr = (void *)A1X_CCM_BASE + (periph >> 5);
+	reg32 = read32(addr);
+	reg32 |= 1 << (periph & 0x1f);
+	write32(reg32, addr);
+}
+
+/**
+ * \brief Disable the clock source for the peripheral
+ *
+ * @param[in] periph peripheral and clock type to disable @see a1x_clken
+ */
+void a1x_periph_clock_disable(enum a1x_clken periph)
+{
+	void *addr;
+	u32 reg32;
+
+	addr = (void *)A1X_CCM_BASE + (periph >> 5);
+	reg32 = read32(addr);
+	reg32 &= ~(1 << (periph & 0x1f));
+	write32(reg32, addr);
+}

src/cpu/allwinner/a10/clock.h

@@ -43,19 +43,108 @@
 #define APB1_RAT_M_MASK			0x1f << 0)
 #define  APB1_RAT_M(n)			(((n) & 0x1f) << 0)
 
-/* APB0_GATING values */
-#define APB0_GATE_KEYPAD		(1 << 10)
-#define APB0_GATE_IR(x)			(((1 << (x)) & 0x3) << 6)
-#define APB0_GATE_PIO			(1 << 5)
-#define APB0_GATE_IIS			(1 << 3)
-#define APB0_GATE_AC97			(1 << 2)
-#define APB0_GATE_CODEC			(1 << 0)
+/**
+ * \brief Clock gating definitions
+ *
+ * The definitions are specified in the form:
+ * 31:5 register offset from A1X_CCM_BASE for the clock register
+ * 4:0  bit offset for the given peripheral
+ *
+ * The names have the form [periph_type][periph_number]
+ *
+ * These definitions are meant to be used with @ref a1x_periph_clock_enable and
+ * @ref a1x_periph_clock_disable
+ */
 
-/* APB1_GATING values */
-#define APB1_GATE_UART(x)		(((1 << (x)) & 0xff) << 16)
-#define APB1_GATE_PS2(x)		(((1 << (x)) & 0x3) << 6)
-#define APB1_GATE_CAN			(1 << 4)
-#define APB1_GATE_TWI(x)		(((1 << (x)) & 0x7) << 0)
+enum a1x_clken {
+	/* AXI module clock gating */
+	A1X_CLKEN_DRAM_AXI = (0x5C << 5),
+	/* AHB0 module clock gating */
+	A1X_CLKEN_USB0 = (0x60 << 5),
+	A1X_CLKEN_EHCI0,
+	RSVD_0x60_2,
+	A1X_CLKEN_EHCI1,
+	RSVD_0x60_4,
+	A1X_CLKEN_SS,
+	A1X_CLKEN_DMA,
+	A1X_CLKEN_BIST,
+	A1X_CLKEN_MMC0,
+	A1X_CLKEN_MMC1,
+	A1X_CLKEN_MMC2,
+	A1X_CLKEN_MMC3,
+	A1X_CLKEN_NC,
+	A1X_CLKEN_NAND,
+	A1X_CLKEN_SDRAM,
+	RSVD_0x60_15,
+	A1X_CLKEN_ACE,
+	A1X_CLKEN_EMAC,
+	A1X_CLKEN_TS,
+	RSVD_0x60_19,
+	A1X_CLKEN_SPI0,
+	A1X_CLKEN_SPI1,
+	A1X_CLKEN_SPI2,
+	A1X_CLKEN_SPI3,
+	A1X_CLKEN_PATA,
+	/* AHB1 module clock gating */
+	A1X_CLKEN_DRAM_VE = (0x64 << 5),
+	A1X_CLKEN_TVD,
+	A1X_CLKEN_TVE0,
+	A1X_CLKEN_TVE1,
+	A1X_CLKEN_LCD0,
+	A1X_CLKEN_LCD1,
+	RSVD_0x64_6,
+	RSVD_0x64_7,
+	A1X_CLKEN_CSI0,
+	A1X_CLKEN_CSI1,
+	RSVD_0x64_10,
+	A1X_CLKEN_HDMI,
+	A1X_CLKEN_DE_BE0,
+	A1X_CLKEN_DE_BE1,
+	A1X_CLKEN_DE_FE0,
+	A1X_CLKEN_DE_FE1,
+	RSVD_0x64_16,
+	RSVD_0x64_17,
+	A1X_CLKEN_MP,
+	RSVD_0x64_19,
+	A1X_CLKEN_MALI400,
+	/* APB0 module clock gating */
+	A1X_CLKEN_CODEC = (0x68 << 5),
+	A1X_CLKEN_NC_APB,
+	A1X_CLKEN_AC97,
+	A1X_CLKEN_IIS,
+	RSVD_0x68_4,
+	A1X_CLKEN_PIO,
+	A1X_CLKEN_IR0,
+	A1X_CLKEN_IR1,
+	RSVD_0x68_8,
+	RSVD_0x68_9,
+	A1X_CLKEN_KEYPAD,
+	/* APB1 module clock gating */
+	A1X_CLKEN_TWI0 = (0x6C << 5),
+	A1X_CLKEN_TWI1,
+	A1X_CLKEN_TWI2,
+	RSVD_0x6C_3,
+	A1X_CLKEN_CAN,
+	A1X_CLKEN_SCR,
+	A1X_CLKEN_PS20,
+	A1X_CLKEN_PS21,
+	RSVD_0x6C_8,
+	RSVD_0x6C_9,
+	RSVD_0x6C_10,
+	RSVD_0x6C_11,
+	RSVD_0x6C_12,
+	RSVD_0x6C_13,
+	RSVD_0x6C_14,
+	RSVD_0x6C_15,
+	A1X_CLKEN_UART0,
+	A1X_CLKEN_UART1,
+	A1X_CLKEN_UART2,
+	A1X_CLKEN_UART3,
+	A1X_CLKEN_UART4,
+	A1X_CLKEN_UART5,
+	A1X_CLKEN_UART6,
+	A1X_CLKEN_UART7,
+};
 
 struct a10_ccm {
 	u32 pll1_cfg;		/* 0x00 pll1 control */
@@ -134,4 +223,7 @@ struct a10_ccm {
 	u32 mbus_clk_cfg;	/* 0x15c */
 } __attribute__ ((packed));
 
+void a1x_periph_clock_enable(enum a1x_clken periph);
+void a1x_periph_clock_disable(enum a1x_clken periph);
+
 #endif				/* CPU_ALLWINNER_A10_CLOCK_H */

src/mainboard/cubietech/cubieboard/bootblock.c

@@ -62,12 +62,7 @@ static void cubieboard_setup_gpios(void)
 
 static void cubieboard_enable_uart(void)
 {
-	u32 reg32;
-	struct a10_ccm *ccm = (void *)A1X_CCM_BASE;
-	/* Enable clock to UART0 */
-	reg32 = read32(&ccm->apb1_gate);
-	reg32 |= APB1_GATE_UART(0);
-	write32(reg32, &ccm->apb1_gate);
+	a1x_periph_clock_enable(A1X_CLKEN_UART0);
 }
 
 void bootblock_mainboard_init(void);