/*
* 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 <[email protected]>
* Copyright (C) 2006 Felix Fietkau <[email protected]>
* Copyright (C) 2012 Alexandros C. Couloumbis <[email protected]>
*/
/*
* 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/memblock.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 void ar2315_misc_irq_handler(struct irq_desc *desc)
{
u32 pending = ar2315_rst_reg_read(AR2315_ISR) &
ar2315_rst_reg_read(AR2315_IMR);
unsigned nr;
int ret = 0;
if (pending) {
struct irq_domain *domain = irq_desc_get_handler_data(desc);
nr = __ffs(pending);
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);
ret = generic_handle_domain_irq(domain, nr);
}
if (!pending || ret)
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 const 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);
if (request_irq(irq, ar2315_ahb_err_handler, 0, "ar2315-ahb-error",
NULL))
pr_err("Failed to register ar2315-ahb-error interrupt\n");
irq_set_chained_handler_and_data(AR2315_IRQ_MISC,
ar2315_misc_irq_handler, 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(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;
memblock_add(0, memsize);
iounmap(sdram_base);
ar2315_rst_base = ioremap(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
}
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