MIPS: ath25: add basic AR5312 SoC support

Add basic support for Atheros AR5312/AR2312 SoCs: registers definition
file and initial setup code.

Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Cc: Linux MIPS <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/8238/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

6 files changed, 386 insertions, 0 deletions

diff --git a/arch/mips/ath25/Kconfig b/arch/mips/ath25/Kconfig
new file mode 100644
index 00000000000..cf933ea3804
--- /dev/null
+++ b/arch/mips/ath25/Kconfig
@@ -0,0 +1,4 @@
+config SOC_AR5312
+	bool "Atheros AR5312/AR2312+ SoC support"
+	depends on ATH25
+	default y
diff --git a/arch/mips/ath25/Makefile b/arch/mips/ath25/Makefile
index 9199fa1508d..3361619caa9 100644
--- a/arch/mips/ath25/Makefile
+++ b/arch/mips/ath25/Makefile
@@ -9,3 +9,5 @@
 #
 
 obj-y += board.o prom.o devices.o
+
+obj-$(CONFIG_SOC_AR5312) += ar5312.o
diff --git a/arch/mips/ath25/ar5312.c b/arch/mips/ath25/ar5312.c
new file mode 100644
index 00000000000..c2adaf2cd73
--- /dev/null
+++ b/arch/mips/ath25/ar5312.c
@@ -0,0 +1,155 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2003 Atheros Communications, Inc.,  All Rights Reserved.
+ * Copyright (C) 2006 FON Technology, SL.
+ * Copyright (C) 2006 Imre Kaloz <kaloz@openwrt.org>
+ * Copyright (C) 2006-2009 Felix Fietkau <nbd@openwrt.org>
+ * Copyright (C) 2012 Alexandros C. Couloumbis <alex@ozo.com>
+ */
+
+/*
+ * Platform devices for Atheros AR5312 SoCs
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/reboot.h>
+#include <asm/bootinfo.h>
+#include <asm/reboot.h>
+#include <asm/time.h>
+
+#include "devices.h"
+#include "ar5312.h"
+#include "ar5312_regs.h"
+
+static void __iomem *ar5312_rst_base;
+
+static inline u32 ar5312_rst_reg_read(u32 reg)
+{
+	return __raw_readl(ar5312_rst_base + reg);
+}
+
+static inline void ar5312_rst_reg_write(u32 reg, u32 val)
+{
+	__raw_writel(val, ar5312_rst_base + reg);
+}
+
+static inline void ar5312_rst_reg_mask(u32 reg, u32 mask, u32 val)
+{
+	u32 ret = ar5312_rst_reg_read(reg);
+
+	ret &= ~mask;
+	ret |= val;
+	ar5312_rst_reg_write(reg, ret);
+}
+
+static void ar5312_restart(char *command)
+{
+	/* reset the system */
+	local_irq_disable();
+	while (1)
+		ar5312_rst_reg_write(AR5312_RESET, AR5312_RESET_SYSTEM);
+}
+
+/*
+ * This table is indexed by bits 5..4 of the CLOCKCTL1 register
+ * to determine the predevisor value.
+ */
+static unsigned clockctl1_predivide_table[4] __initdata = { 1, 2, 4, 5 };
+
+static unsigned __init ar5312_cpu_frequency(void)
+{
+	u32 scratch, devid, clock_ctl1;
+	u32 predivide_mask, multiplier_mask, doubler_mask;
+	unsigned predivide_shift, multiplier_shift;
+	unsigned predivide_select, predivisor, multiplier;
+
+	/* Trust the bootrom's idea of cpu frequency. */
+	scratch = ar5312_rst_reg_read(AR5312_SCRATCH);
+	if (scratch)
+		return scratch;
+
+	devid = ar5312_rst_reg_read(AR5312_REV);
+	devid = (devid & AR5312_REV_MAJ) >> AR5312_REV_MAJ_S;
+	if (devid == AR5312_REV_MAJ_AR2313) {
+		predivide_mask = AR2313_CLOCKCTL1_PREDIVIDE_MASK;
+		predivide_shift = AR2313_CLOCKCTL1_PREDIVIDE_SHIFT;
+		multiplier_mask = AR2313_CLOCKCTL1_MULTIPLIER_MASK;
+		multiplier_shift = AR2313_CLOCKCTL1_MULTIPLIER_SHIFT;
+		doubler_mask = AR2313_CLOCKCTL1_DOUBLER_MASK;
+	} else { /* AR5312 and AR2312 */
+		predivide_mask = AR5312_CLOCKCTL1_PREDIVIDE_MASK;
+		predivide_shift = AR5312_CLOCKCTL1_PREDIVIDE_SHIFT;
+		multiplier_mask = AR5312_CLOCKCTL1_MULTIPLIER_MASK;
+		multiplier_shift = AR5312_CLOCKCTL1_MULTIPLIER_SHIFT;
+		doubler_mask = AR5312_CLOCKCTL1_DOUBLER_MASK;
+	}
+
+	/*
+	 * Clocking is derived from a fixed 40MHz input clock.
+	 *
+	 *  cpu_freq = input_clock * MULT (where MULT is PLL multiplier)
+	 *  sys_freq = cpu_freq / 4	  (used for APB clock, serial,
+	 *				   flash, Timer, Watchdog Timer)
+	 *
+	 *  cnt_freq = cpu_freq / 2	  (use for CPU count/compare)
+	 *
+	 * So, for example, with a PLL multiplier of 5, we have
+	 *
+	 *  cpu_freq = 200MHz
+	 *  sys_freq = 50MHz
+	 *  cnt_freq = 100MHz
+	 *
+	 * We compute the CPU frequency, based on PLL settings.
+	 */
+
+	clock_ctl1 = ar5312_rst_reg_read(AR5312_CLOCKCTL1);
+	predivide_select = (clock_ctl1 & predivide_mask) >> predivide_shift;
+	predivisor = clockctl1_predivide_table[predivide_select];
+	multiplier = (clock_ctl1 & multiplier_mask) >> multiplier_shift;
+
+	if (clock_ctl1 & doubler_mask)
+		multiplier <<= 1;
+
+	return (40000000 / predivisor) * multiplier;
+}
+
+static inline unsigned ar5312_sys_frequency(void)
+{
+	return ar5312_cpu_frequency() / 4;
+}
+
+void __init ar5312_plat_time_init(void)
+{
+	mips_hpt_frequency = ar5312_cpu_frequency() / 2;
+}
+
+void __init ar5312_plat_mem_setup(void)
+{
+	void __iomem *sdram_base;
+	u32 memsize, memcfg, bank0_ac, bank1_ac;
+
+	/* Detect memory size */
+	sdram_base = ioremap_nocache(AR5312_SDRAMCTL_BASE,
+				     AR5312_SDRAMCTL_SIZE);
+	memcfg = __raw_readl(sdram_base + AR5312_MEM_CFG1);
+	bank0_ac = ATH25_REG_MS(memcfg, AR5312_MEM_CFG1_AC0);
+	bank1_ac = ATH25_REG_MS(memcfg, AR5312_MEM_CFG1_AC1);
+	memsize = (bank0_ac ? (1 << (bank0_ac + 1)) : 0) +
+		  (bank1_ac ? (1 << (bank1_ac + 1)) : 0);
+	memsize <<= 20;
+	add_memory_region(0, memsize, BOOT_MEM_RAM);
+	iounmap(sdram_base);
+
+	ar5312_rst_base = ioremap_nocache(AR5312_RST_BASE, AR5312_RST_SIZE);
+
+	/* Clear any lingering AHB errors */
+	ar5312_rst_reg_read(AR5312_PROCADDR);
+	ar5312_rst_reg_read(AR5312_DMAADDR);
+	ar5312_rst_reg_write(AR5312_WDT_CTRL, AR5312_WDT_CTRL_IGNORE);
+
+	_machine_restart = ar5312_restart;
+}
diff --git a/arch/mips/ath25/ar5312.h b/arch/mips/ath25/ar5312.h
new file mode 100644
index 00000000000..9e1e56e24ee
--- /dev/null
+++ b/arch/mips/ath25/ar5312.h
@@ -0,0 +1,16 @@
+#ifndef __AR5312_H
+#define __AR5312_H
+
+#ifdef CONFIG_SOC_AR5312
+
+void ar5312_plat_time_init(void);
+void ar5312_plat_mem_setup(void);
+
+#else
+
+static inline void ar5312_plat_time_init(void) {}
+static inline void ar5312_plat_mem_setup(void) {}
+
+#endif
+
+#endif	/* __AR5312_H */
diff --git a/arch/mips/ath25/ar5312_regs.h b/arch/mips/ath25/ar5312_regs.h
new file mode 100644
index 00000000000..ff1201119be
--- /dev/null
+++ b/arch/mips/ath25/ar5312_regs.h
@@ -0,0 +1,201 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2003 Atheros Communications, Inc.,  All Rights Reserved.
+ * Copyright (C) 2006 Imre Kaloz <kaloz@openwrt.org>
+ * Copyright (C) 2006 Felix Fietkau <nbd@openwrt.org>
+ */
+
+#ifndef __ASM_MACH_ATH25_AR5312_REGS_H
+#define __ASM_MACH_ATH25_AR5312_REGS_H
+
+/*
+ * Address Map
+ *
+ * The AR5312 supports 2 enet MACS, even though many reference boards only
+ * actually use 1 of them (i.e. Only MAC 0 is actually connected to an enet
+ * PHY or PHY switch. The AR2312 supports 1 enet MAC.
+ */
+#define AR5312_WLAN0_BASE		0x18000000
+#define AR5312_ENET0_BASE		0x18100000
+#define AR5312_ENET1_BASE		0x18200000
+#define AR5312_SDRAMCTL_BASE		0x18300000
+#define AR5312_SDRAMCTL_SIZE		0x00000010
+#define AR5312_FLASHCTL_BASE		0x18400000
+#define AR5312_FLASHCTL_SIZE		0x00000010
+#define AR5312_WLAN1_BASE		0x18500000
+#define AR5312_UART0_BASE		0x1c000000	/* UART MMR */
+#define AR5312_GPIO_BASE		0x1c002000
+#define AR5312_GPIO_SIZE		0x00000010
+#define AR5312_RST_BASE			0x1c003000
+#define AR5312_RST_SIZE			0x00000100
+#define AR5312_FLASH_BASE		0x1e000000
+#define AR5312_FLASH_SIZE		0x00800000
+
+/*
+ * Need these defines to determine true number of ethernet MACs
+ */
+#define AR5312_AR5312_REV2	0x0052		/* AR5312 WMAC (AP31) */
+#define AR5312_AR5312_REV7	0x0057		/* AR5312 WMAC (AP30-040) */
+#define AR5312_AR2313_REV8	0x0058		/* AR2313 WMAC (AP43-030) */
+
+/* Reset/Timer Block Address Map */
+#define AR5312_TIMER		0x0000 /* countdown timer */
+#define AR5312_RELOAD		0x0004 /* timer reload value */
+#define AR5312_WDT_CTRL		0x0008 /* watchdog cntrl */
+#define AR5312_WDT_TIMER	0x000c /* watchdog timer */
+#define AR5312_ISR		0x0010 /* Intr Status Reg */
+#define AR5312_IMR		0x0014 /* Intr Mask Reg */
+#define AR5312_RESET		0x0020
+#define AR5312_CLOCKCTL1	0x0064
+#define AR5312_SCRATCH		0x006c
+#define AR5312_PROCADDR		0x0070
+#define AR5312_PROC1		0x0074
+#define AR5312_DMAADDR		0x0078
+#define AR5312_DMA1		0x007c
+#define AR5312_ENABLE		0x0080 /* interface enb */
+#define AR5312_REV		0x0090 /* revision */
+
+/* AR5312_WDT_CTRL register bit field definitions */
+#define AR5312_WDT_CTRL_IGNORE	0x00000000	/* ignore expiration */
+#define AR5312_WDT_CTRL_NMI	0x00000001
+#define AR5312_WDT_CTRL_RESET	0x00000002
+
+/* AR5312_ISR register bit field definitions */
+#define AR5312_ISR_TIMER	0x00000001
+#define AR5312_ISR_AHBPROC	0x00000002
+#define AR5312_ISR_AHBDMA	0x00000004
+#define AR5312_ISR_GPIO		0x00000008
+#define AR5312_ISR_UART0	0x00000010
+#define AR5312_ISR_UART0DMA	0x00000020
+#define AR5312_ISR_WD		0x00000040
+#define AR5312_ISR_LOCAL	0x00000080
+
+/* AR5312_RESET register bit field definitions */
+#define AR5312_RESET_SYSTEM		0x00000001  /* cold reset full system */
+#define AR5312_RESET_PROC		0x00000002  /* cold reset MIPS core */
+#define AR5312_RESET_WLAN0		0x00000004  /* cold reset WLAN MAC/BB */
+#define AR5312_RESET_EPHY0		0x00000008  /* cold reset ENET0 phy */
+#define AR5312_RESET_EPHY1		0x00000010  /* cold reset ENET1 phy */
+#define AR5312_RESET_ENET0		0x00000020  /* cold reset ENET0 MAC */
+#define AR5312_RESET_ENET1		0x00000040  /* cold reset ENET1 MAC */
+#define AR5312_RESET_UART0		0x00000100  /* cold reset UART0 */
+#define AR5312_RESET_WLAN1		0x00000200  /* cold reset WLAN MAC/BB */
+#define AR5312_RESET_APB		0x00000400  /* cold reset APB ar5312 */
+#define AR5312_RESET_WARM_PROC		0x00001000  /* warm reset MIPS core */
+#define AR5312_RESET_WARM_WLAN0_MAC	0x00002000  /* warm reset WLAN0 MAC */
+#define AR5312_RESET_WARM_WLAN0_BB	0x00004000  /* warm reset WLAN0 BB */
+#define AR5312_RESET_NMI		0x00010000  /* send an NMI to the CPU */
+#define AR5312_RESET_WARM_WLAN1_MAC	0x00020000  /* warm reset WLAN1 MAC */
+#define AR5312_RESET_WARM_WLAN1_BB	0x00040000  /* warm reset WLAN1 BB */
+#define AR5312_RESET_LOCAL_BUS		0x00080000  /* reset local bus */
+#define AR5312_RESET_WDOG		0x00100000  /* last reset was a wdt */
+
+#define AR5312_RESET_WMAC0_BITS		(AR5312_RESET_WLAN0 |\
+					 AR5312_RESET_WARM_WLAN0_MAC |\
+					 AR5312_RESET_WARM_WLAN0_BB)
+
+#define AR5312_RESET_WMAC1_BITS		(AR5312_RESET_WLAN1 |\
+					 AR5312_RESET_WARM_WLAN1_MAC |\
+					 AR5312_RESET_WARM_WLAN1_BB)
+
+/* AR5312_CLOCKCTL1 register bit field definitions */
+#define AR5312_CLOCKCTL1_PREDIVIDE_MASK		0x00000030
+#define AR5312_CLOCKCTL1_PREDIVIDE_SHIFT	4
+#define AR5312_CLOCKCTL1_MULTIPLIER_MASK	0x00001f00
+#define AR5312_CLOCKCTL1_MULTIPLIER_SHIFT	8
+#define AR5312_CLOCKCTL1_DOUBLER_MASK		0x00010000
+
+/* Valid for AR5312 and AR2312 */
+#define AR5312_CLOCKCTL1_PREDIVIDE_MASK		0x00000030
+#define AR5312_CLOCKCTL1_PREDIVIDE_SHIFT	4
+#define AR5312_CLOCKCTL1_MULTIPLIER_MASK	0x00001f00
+#define AR5312_CLOCKCTL1_MULTIPLIER_SHIFT	8
+#define AR5312_CLOCKCTL1_DOUBLER_MASK		0x00010000
+
+/* Valid for AR2313 */
+#define AR2313_CLOCKCTL1_PREDIVIDE_MASK		0x00003000
+#define AR2313_CLOCKCTL1_PREDIVIDE_SHIFT	12
+#define AR2313_CLOCKCTL1_MULTIPLIER_MASK	0x001f0000
+#define AR2313_CLOCKCTL1_MULTIPLIER_SHIFT	16
+#define AR2313_CLOCKCTL1_DOUBLER_MASK		0x00000000
+
+/* AR5312_ENABLE register bit field definitions */
+#define AR5312_ENABLE_WLAN0			0x00000001
+#define AR5312_ENABLE_ENET0			0x00000002
+#define AR5312_ENABLE_ENET1			0x00000004
+#define AR5312_ENABLE_UART_AND_WLAN1_PIO	0x00000008/* UART & WLAN1 PIO */
+#define AR5312_ENABLE_WLAN1_DMA			0x00000010/* WLAN1 DMAs */
+#define AR5312_ENABLE_WLAN1		(AR5312_ENABLE_UART_AND_WLAN1_PIO |\
+					 AR5312_ENABLE_WLAN1_DMA)
+
+/* AR5312_REV register bit field definitions */
+#define AR5312_REV_WMAC_MAJ	0x0000f000
+#define AR5312_REV_WMAC_MAJ_S	12
+#define AR5312_REV_WMAC_MIN	0x00000f00
+#define AR5312_REV_WMAC_MIN_S	8
+#define AR5312_REV_MAJ		0x000000f0
+#define AR5312_REV_MAJ_S	4
+#define AR5312_REV_MIN		0x0000000f
+#define AR5312_REV_MIN_S	0
+#define AR5312_REV_CHIP		(AR5312_REV_MAJ|AR5312_REV_MIN)
+
+/* Major revision numbers, bits 7..4 of Revision ID register */
+#define AR5312_REV_MAJ_AR5312		0x4
+#define AR5312_REV_MAJ_AR2313		0x5
+
+/* Minor revision numbers, bits 3..0 of Revision ID register */
+#define AR5312_REV_MIN_DUAL		0x0	/* Dual WLAN version */
+#define AR5312_REV_MIN_SINGLE		0x1	/* Single WLAN version */
+
+/*
+ * ARM Flash Controller -- 3 flash banks with either x8 or x16 devices
+ */
+#define AR5312_FLASHCTL0	0x0000
+#define AR5312_FLASHCTL1	0x0004
+#define AR5312_FLASHCTL2	0x0008
+
+/* AR5312_FLASHCTL register bit field definitions */
+#define AR5312_FLASHCTL_IDCY	0x0000000f	/* Idle cycle turnaround time */
+#define AR5312_FLASHCTL_IDCY_S	0
+#define AR5312_FLASHCTL_WST1	0x000003e0	/* Wait state 1 */
+#define AR5312_FLASHCTL_WST1_S	5
+#define AR5312_FLASHCTL_RBLE	0x00000400	/* Read byte lane enable */
+#define AR5312_FLASHCTL_WST2	0x0000f800	/* Wait state 2 */
+#define AR5312_FLASHCTL_WST2_S	11
+#define AR5312_FLASHCTL_AC	0x00070000	/* Flash addr check (added) */
+#define AR5312_FLASHCTL_AC_S	16
+#define AR5312_FLASHCTL_AC_128K	0x00000000
+#define AR5312_FLASHCTL_AC_256K	0x00010000
+#define AR5312_FLASHCTL_AC_512K	0x00020000
+#define AR5312_FLASHCTL_AC_1M	0x00030000
+#define AR5312_FLASHCTL_AC_2M	0x00040000
+#define AR5312_FLASHCTL_AC_4M	0x00050000
+#define AR5312_FLASHCTL_AC_8M	0x00060000
+#define AR5312_FLASHCTL_AC_RES	0x00070000	/* 16MB is not supported */
+#define AR5312_FLASHCTL_E	0x00080000	/* Flash bank enable (added) */
+#define AR5312_FLASHCTL_BUSERR	0x01000000	/* Bus transfer error flag */
+#define AR5312_FLASHCTL_WPERR	0x02000000	/* Write protect error flag */
+#define AR5312_FLASHCTL_WP	0x04000000	/* Write protect */
+#define AR5312_FLASHCTL_BM	0x08000000	/* Burst mode */
+#define AR5312_FLASHCTL_MW	0x30000000	/* Mem width */
+#define AR5312_FLASHCTL_MW8	0x00000000	/* Mem width x8 */
+#define AR5312_FLASHCTL_MW16	0x10000000	/* Mem width x16 */
+#define AR5312_FLASHCTL_MW32	0x20000000	/* Mem width x32 (not supp) */
+#define AR5312_FLASHCTL_ATNR	0x00000000	/* Access == no retry */
+#define AR5312_FLASHCTL_ATR	0x80000000	/* Access == retry every */
+#define AR5312_FLASHCTL_ATR4	0xc0000000	/* Access == retry every 4 */
+
+/*
+ * ARM SDRAM Controller -- just enough to determine memory size
+ */
+#define AR5312_MEM_CFG1		0x0004
+
+#define AR5312_MEM_CFG1_AC0_M	0x00000700	/* bank 0: SDRAM addr check */
+#define AR5312_MEM_CFG1_AC0_S	8
+#define AR5312_MEM_CFG1_AC1_M	0x00007000	/* bank 1: SDRAM addr check */
+#define AR5312_MEM_CFG1_AC1_S	12
+
+#endif	/* __ASM_MACH_ATH25_AR5312_REGS_H */
diff --git a/arch/mips/ath25/board.c b/arch/mips/ath25/board.c
index dd70327fd80..03baeceb3e3 100644
--- a/arch/mips/ath25/board.c
+++ b/arch/mips/ath25/board.c
@@ -16,6 +16,9 @@
 #include <asm/bootinfo.h>
 #include <asm/time.h>
 
+#include "devices.h"
+#include "ar5312.h"
+
 static void ath25_halt(void)
 {
 	local_irq_disable();
@@ -27,6 +30,9 @@ void __init plat_mem_setup(void)
 	_machine_halt = ath25_halt;
 	pm_power_off = ath25_halt;
 
+	if (is_ar5312())
+		ar5312_plat_mem_setup();
+
 	/* Disable data watchpoints */
 	write_c0_watchlo0(0);
 }
@@ -37,6 +43,8 @@ asmlinkage void plat_irq_dispatch(void)
 
 void __init plat_time_init(void)
 {
+	if (is_ar5312())
+		ar5312_plat_time_init();
 }
 
 unsigned int __cpuinit get_c0_compare_int(void)