Initial import

1 files changed, 364 insertions, 0 deletions

diff --git a/arch/mips/ath25/ar2315.c b/arch/mips/ath25/ar2315.c
new file mode 100644
index 000000000..2befa7d76
--- /dev/null
+++ b/arch/mips/ath25/ar2315.c
@@ -0,0 +1,364 @@
+/*
+ * 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 Felix Fietkau <nbd@openwrt.org>
+ * Copyright (C) 2012 Alexandros C. Couloumbis <alex@ozo.com>
+ */
+
+/*
+ * Platform devices for Atheros AR2315 SoCs
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/bitops.h>
+#include <linux/irqdomain.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/reboot.h>
+#include <asm/bootinfo.h>
+#include <asm/reboot.h>
+#include <asm/time.h>
+
+#include <ath25_platform.h>
+
+#include "devices.h"
+#include "ar2315.h"
+#include "ar2315_regs.h"
+
+static void __iomem *ar2315_rst_base;
+static struct irq_domain *ar2315_misc_irq_domain;
+
+static inline u32 ar2315_rst_reg_read(u32 reg)
+{
+	return __raw_readl(ar2315_rst_base + reg);
+}
+
+static inline void ar2315_rst_reg_write(u32 reg, u32 val)
+{
+	__raw_writel(val, ar2315_rst_base + reg);
+}
+
+static inline void ar2315_rst_reg_mask(u32 reg, u32 mask, u32 val)
+{
+	u32 ret = ar2315_rst_reg_read(reg);
+
+	ret &= ~mask;
+	ret |= val;
+	ar2315_rst_reg_write(reg, ret);
+}
+
+static irqreturn_t ar2315_ahb_err_handler(int cpl, void *dev_id)
+{
+	ar2315_rst_reg_write(AR2315_AHB_ERR0, AR2315_AHB_ERROR_DET);
+	ar2315_rst_reg_read(AR2315_AHB_ERR1);
+
+	pr_emerg("AHB fatal error\n");
+	machine_restart("AHB error"); /* Catastrophic failure */
+
+	return IRQ_HANDLED;
+}
+
+static struct irqaction ar2315_ahb_err_interrupt  = {
+	.handler	= ar2315_ahb_err_handler,
+	.name		= "ar2315-ahb-error",
+};
+
+static void ar2315_misc_irq_handler(unsigned irq, struct irq_desc *desc)
+{
+	u32 pending = ar2315_rst_reg_read(AR2315_ISR) &
+		      ar2315_rst_reg_read(AR2315_IMR);
+	unsigned nr, misc_irq = 0;
+
+	if (pending) {
+		struct irq_domain *domain = irq_get_handler_data(irq);
+
+		nr = __ffs(pending);
+		misc_irq = irq_find_mapping(domain, nr);
+	}
+
+	if (misc_irq) {
+		if (nr == AR2315_MISC_IRQ_GPIO)
+			ar2315_rst_reg_write(AR2315_ISR, AR2315_ISR_GPIO);
+		else if (nr == AR2315_MISC_IRQ_WATCHDOG)
+			ar2315_rst_reg_write(AR2315_ISR, AR2315_ISR_WD);
+		generic_handle_irq(misc_irq);
+	} else {
+		spurious_interrupt();
+	}
+}
+
+static void ar2315_misc_irq_unmask(struct irq_data *d)
+{
+	ar2315_rst_reg_mask(AR2315_IMR, 0, BIT(d->hwirq));
+}
+
+static void ar2315_misc_irq_mask(struct irq_data *d)
+{
+	ar2315_rst_reg_mask(AR2315_IMR, BIT(d->hwirq), 0);
+}
+
+static struct irq_chip ar2315_misc_irq_chip = {
+	.name		= "ar2315-misc",
+	.irq_unmask	= ar2315_misc_irq_unmask,
+	.irq_mask	= ar2315_misc_irq_mask,
+};
+
+static int ar2315_misc_irq_map(struct irq_domain *d, unsigned irq,
+			       irq_hw_number_t hw)
+{
+	irq_set_chip_and_handler(irq, &ar2315_misc_irq_chip, handle_level_irq);
+	return 0;
+}
+
+static struct irq_domain_ops ar2315_misc_irq_domain_ops = {
+	.map = ar2315_misc_irq_map,
+};
+
+/*
+ * Called when an interrupt is received, this function
+ * determines exactly which interrupt it was, and it
+ * invokes the appropriate handler.
+ *
+ * Implicitly, we also define interrupt priority by
+ * choosing which to dispatch first.
+ */
+static void ar2315_irq_dispatch(void)
+{
+	u32 pending = read_c0_status() & read_c0_cause();
+
+	if (pending & CAUSEF_IP3)
+		do_IRQ(AR2315_IRQ_WLAN0);
+#ifdef CONFIG_PCI_AR2315
+	else if (pending & CAUSEF_IP5)
+		do_IRQ(AR2315_IRQ_LCBUS_PCI);
+#endif
+	else if (pending & CAUSEF_IP2)
+		do_IRQ(AR2315_IRQ_MISC);
+	else if (pending & CAUSEF_IP7)
+		do_IRQ(ATH25_IRQ_CPU_CLOCK);
+	else
+		spurious_interrupt();
+}
+
+void __init ar2315_arch_init_irq(void)
+{
+	struct irq_domain *domain;
+	unsigned irq;
+
+	ath25_irq_dispatch = ar2315_irq_dispatch;
+
+	domain = irq_domain_add_linear(NULL, AR2315_MISC_IRQ_COUNT,
+				       &ar2315_misc_irq_domain_ops, NULL);
+	if (!domain)
+		panic("Failed to add IRQ domain");
+
+	irq = irq_create_mapping(domain, AR2315_MISC_IRQ_AHB);
+	setup_irq(irq, &ar2315_ahb_err_interrupt);
+
+	irq_set_chained_handler(AR2315_IRQ_MISC, ar2315_misc_irq_handler);
+	irq_set_handler_data(AR2315_IRQ_MISC, domain);
+
+	ar2315_misc_irq_domain = domain;
+}
+
+void __init ar2315_init_devices(void)
+{
+	/* Find board configuration */
+	ath25_find_config(AR2315_SPI_READ_BASE, AR2315_SPI_READ_SIZE);
+
+	ath25_add_wmac(0, AR2315_WLAN0_BASE, AR2315_IRQ_WLAN0);
+}
+
+static void ar2315_restart(char *command)
+{
+	void (*mips_reset_vec)(void) = (void *)0xbfc00000;
+
+	local_irq_disable();
+
+	/* try reset the system via reset control */
+	ar2315_rst_reg_write(AR2315_COLD_RESET, AR2317_RESET_SYSTEM);
+
+	/* Cold reset does not work on the AR2315/6, use the GPIO reset bits
+	 * a workaround. Give it some time to attempt a gpio based hardware
+	 * reset (atheros reference design workaround) */
+
+	/* TODO: implement the GPIO reset workaround */
+
+	/* Some boards (e.g. Senao EOC-2610) don't implement the reset logic
+	 * workaround. Attempt to jump to the mips reset location -
+	 * the boot loader itself might be able to recover the system */
+	mips_reset_vec();
+}
+
+/*
+ * This table is indexed by bits 5..4 of the CLOCKCTL1 register
+ * to determine the predevisor value.
+ */
+static int clockctl1_predivide_table[4] __initdata = { 1, 2, 4, 5 };
+static int pllc_divide_table[5] __initdata = { 2, 3, 4, 6, 3 };
+
+static unsigned __init ar2315_sys_clk(u32 clock_ctl)
+{
+	unsigned int pllc_ctrl, cpu_div;
+	unsigned int pllc_out, refdiv, fdiv, divby2;
+	unsigned int clk_div;
+
+	pllc_ctrl = ar2315_rst_reg_read(AR2315_PLLC_CTL);
+	refdiv = ATH25_REG_MS(pllc_ctrl, AR2315_PLLC_REF_DIV);
+	refdiv = clockctl1_predivide_table[refdiv];
+	fdiv = ATH25_REG_MS(pllc_ctrl, AR2315_PLLC_FDBACK_DIV);
+	divby2 = ATH25_REG_MS(pllc_ctrl, AR2315_PLLC_ADD_FDBACK_DIV) + 1;
+	pllc_out = (40000000 / refdiv) * (2 * divby2) * fdiv;
+
+	/* clkm input selected */
+	switch (clock_ctl & AR2315_CPUCLK_CLK_SEL_M) {
+	case 0:
+	case 1:
+		clk_div = ATH25_REG_MS(pllc_ctrl, AR2315_PLLC_CLKM_DIV);
+		clk_div = pllc_divide_table[clk_div];
+		break;
+	case 2:
+		clk_div = ATH25_REG_MS(pllc_ctrl, AR2315_PLLC_CLKC_DIV);
+		clk_div = pllc_divide_table[clk_div];
+		break;
+	default:
+		pllc_out = 40000000;
+		clk_div = 1;
+		break;
+	}
+
+	cpu_div = ATH25_REG_MS(clock_ctl, AR2315_CPUCLK_CLK_DIV);
+	cpu_div = cpu_div * 2 ?: 1;
+
+	return pllc_out / (clk_div * cpu_div);
+}
+
+static inline unsigned ar2315_cpu_frequency(void)
+{
+	return ar2315_sys_clk(ar2315_rst_reg_read(AR2315_CPUCLK));
+}
+
+static inline unsigned ar2315_apb_frequency(void)
+{
+	return ar2315_sys_clk(ar2315_rst_reg_read(AR2315_AMBACLK));
+}
+
+void __init ar2315_plat_time_init(void)
+{
+	mips_hpt_frequency = ar2315_cpu_frequency() / 2;
+}
+
+void __init ar2315_plat_mem_setup(void)
+{
+	void __iomem *sdram_base;
+	u32 memsize, memcfg;
+	u32 devid;
+	u32 config;
+
+	/* Detect memory size */
+	sdram_base = ioremap_nocache(AR2315_SDRAMCTL_BASE,
+				     AR2315_SDRAMCTL_SIZE);
+	memcfg = __raw_readl(sdram_base + AR2315_MEM_CFG);
+	memsize   = 1 + ATH25_REG_MS(memcfg, AR2315_MEM_CFG_DATA_WIDTH);
+	memsize <<= 1 + ATH25_REG_MS(memcfg, AR2315_MEM_CFG_COL_WIDTH);
+	memsize <<= 1 + ATH25_REG_MS(memcfg, AR2315_MEM_CFG_ROW_WIDTH);
+	memsize <<= 3;
+	add_memory_region(0, memsize, BOOT_MEM_RAM);
+	iounmap(sdram_base);
+
+	ar2315_rst_base = ioremap_nocache(AR2315_RST_BASE, AR2315_RST_SIZE);
+
+	/* Detect the hardware based on the device ID */
+	devid = ar2315_rst_reg_read(AR2315_SREV) & AR2315_REV_CHIP;
+	switch (devid) {
+	case 0x91:	/* Need to check */
+		ath25_soc = ATH25_SOC_AR2318;
+		break;
+	case 0x90:
+		ath25_soc = ATH25_SOC_AR2317;
+		break;
+	case 0x87:
+		ath25_soc = ATH25_SOC_AR2316;
+		break;
+	case 0x86:
+	default:
+		ath25_soc = ATH25_SOC_AR2315;
+		break;
+	}
+	ath25_board.devid = devid;
+
+	/* Clear any lingering AHB errors */
+	config = read_c0_config();
+	write_c0_config(config & ~0x3);
+	ar2315_rst_reg_write(AR2315_AHB_ERR0, AR2315_AHB_ERROR_DET);
+	ar2315_rst_reg_read(AR2315_AHB_ERR1);
+	ar2315_rst_reg_write(AR2315_WDT_CTRL, AR2315_WDT_CTRL_IGNORE);
+
+	_machine_restart = ar2315_restart;
+}
+
+#ifdef CONFIG_PCI_AR2315
+static struct resource ar2315_pci_res[] = {
+	{
+		.name = "ar2315-pci-ctrl",
+		.flags = IORESOURCE_MEM,
+		.start = AR2315_PCI_BASE,
+		.end = AR2315_PCI_BASE + AR2315_PCI_SIZE - 1,
+	},
+	{
+		.name = "ar2315-pci-ext",
+		.flags = IORESOURCE_MEM,
+		.start = AR2315_PCI_EXT_BASE,
+		.end = AR2315_PCI_EXT_BASE + AR2315_PCI_EXT_SIZE - 1,
+	},
+	{
+		.name = "ar2315-pci",
+		.flags = IORESOURCE_IRQ,
+		.start = AR2315_IRQ_LCBUS_PCI,
+		.end = AR2315_IRQ_LCBUS_PCI,
+	},
+};
+#endif
+
+void __init ar2315_arch_init(void)
+{
+	unsigned irq = irq_create_mapping(ar2315_misc_irq_domain,
+					  AR2315_MISC_IRQ_UART0);
+
+	ath25_serial_setup(AR2315_UART0_BASE, irq, ar2315_apb_frequency());
+
+#ifdef CONFIG_PCI_AR2315
+	if (ath25_soc == ATH25_SOC_AR2315) {
+		/* Reset PCI DMA logic */
+		ar2315_rst_reg_mask(AR2315_RESET, 0, AR2315_RESET_PCIDMA);
+		msleep(20);
+		ar2315_rst_reg_mask(AR2315_RESET, AR2315_RESET_PCIDMA, 0);
+		msleep(20);
+
+		/* Configure endians */
+		ar2315_rst_reg_mask(AR2315_ENDIAN_CTL, 0, AR2315_CONFIG_PCIAHB |
+				    AR2315_CONFIG_PCIAHB_BRIDGE);
+
+		/* Configure as PCI host with DMA */
+		ar2315_rst_reg_write(AR2315_PCICLK, AR2315_PCICLK_PLLC_CLKM |
+				  (AR2315_PCICLK_IN_FREQ_DIV_6 <<
+				   AR2315_PCICLK_DIV_S));
+		ar2315_rst_reg_mask(AR2315_AHB_ARB_CTL, 0, AR2315_ARB_PCI);
+		ar2315_rst_reg_mask(AR2315_IF_CTL, AR2315_IF_PCI_CLK_MASK |
+				    AR2315_IF_MASK, AR2315_IF_PCI |
+				    AR2315_IF_PCI_HOST | AR2315_IF_PCI_INTR |
+				    (AR2315_IF_PCI_CLK_OUTPUT_CLK <<
+				     AR2315_IF_PCI_CLK_SHIFT));
+
+		platform_device_register_simple("ar2315-pci", -1,
+						ar2315_pci_res,
+						ARRAY_SIZE(ar2315_pci_res));
+	}
+#endif
+}