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Diffstat (limited to 'arch/mips/ath25/ar2315.c')
| -rw-r--r-- | arch/mips/ath25/ar2315.c | 364 |
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 +} |