diff options
Diffstat (limited to 'arch/mips/lantiq/xway/gptu.c')
| -rw-r--r-- | arch/mips/lantiq/xway/gptu.c | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/arch/mips/lantiq/xway/gptu.c b/arch/mips/lantiq/xway/gptu.c new file mode 100644 index 0000000000..8d52001301 --- /dev/null +++ b/arch/mips/lantiq/xway/gptu.c @@ -0,0 +1,206 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * + * Copyright (C) 2012 John Crispin <john@phrozen.org> + * Copyright (C) 2012 Lantiq GmbH + */ + +#include <linux/interrupt.h> +#include <linux/ioport.h> +#include <linux/init.h> +#include <linux/mod_devicetable.h> +#include <linux/of_irq.h> +#include <linux/platform_device.h> + +#include <lantiq_soc.h> +#include "../clk.h" + +/* the magic ID byte of the core */ +#define GPTU_MAGIC 0x59 +/* clock control register */ +#define GPTU_CLC 0x00 +/* id register */ +#define GPTU_ID 0x08 +/* interrupt node enable */ +#define GPTU_IRNEN 0xf4 +/* interrupt control register */ +#define GPTU_IRCR 0xf8 +/* interrupt capture register */ +#define GPTU_IRNCR 0xfc +/* there are 3 identical blocks of 2 timers. calculate register offsets */ +#define GPTU_SHIFT(x) (x % 2 ? 4 : 0) +#define GPTU_BASE(x) (((x >> 1) * 0x20) + 0x10) +/* timer control register */ +#define GPTU_CON(x) (GPTU_BASE(x) + GPTU_SHIFT(x) + 0x00) +/* timer auto reload register */ +#define GPTU_RUN(x) (GPTU_BASE(x) + GPTU_SHIFT(x) + 0x08) +/* timer manual reload register */ +#define GPTU_RLD(x) (GPTU_BASE(x) + GPTU_SHIFT(x) + 0x10) +/* timer count register */ +#define GPTU_CNT(x) (GPTU_BASE(x) + GPTU_SHIFT(x) + 0x18) + +/* GPTU_CON(x) */ +#define CON_CNT BIT(2) +#define CON_EDGE_ANY (BIT(7) | BIT(6)) +#define CON_SYNC BIT(8) +#define CON_CLK_INT BIT(10) + +/* GPTU_RUN(x) */ +#define RUN_SEN BIT(0) +#define RUN_RL BIT(2) + +/* set clock to runmode */ +#define CLC_RMC BIT(8) +/* bring core out of suspend */ +#define CLC_SUSPEND BIT(4) +/* the disable bit */ +#define CLC_DISABLE BIT(0) + +#define gptu_w32(x, y) ltq_w32((x), gptu_membase + (y)) +#define gptu_r32(x) ltq_r32(gptu_membase + (x)) + +enum gptu_timer { + TIMER1A = 0, + TIMER1B, + TIMER2A, + TIMER2B, + TIMER3A, + TIMER3B +}; + +static void __iomem *gptu_membase; +static struct resource irqres[6]; + +static irqreturn_t timer_irq_handler(int irq, void *priv) +{ + int timer = irq - irqres[0].start; + gptu_w32(1 << timer, GPTU_IRNCR); + return IRQ_HANDLED; +} + +static void gptu_hwinit(void) +{ + gptu_w32(0x00, GPTU_IRNEN); + gptu_w32(0xff, GPTU_IRNCR); + gptu_w32(CLC_RMC | CLC_SUSPEND, GPTU_CLC); +} + +static void gptu_hwexit(void) +{ + gptu_w32(0x00, GPTU_IRNEN); + gptu_w32(0xff, GPTU_IRNCR); + gptu_w32(CLC_DISABLE, GPTU_CLC); +} + +static int gptu_enable(struct clk *clk) +{ + int ret = request_irq(irqres[clk->bits].start, timer_irq_handler, + IRQF_TIMER, "gtpu", NULL); + if (ret) { + pr_err("gptu: failed to request irq\n"); + return ret; + } + + gptu_w32(CON_CNT | CON_EDGE_ANY | CON_SYNC | CON_CLK_INT, + GPTU_CON(clk->bits)); + gptu_w32(1, GPTU_RLD(clk->bits)); + gptu_w32(gptu_r32(GPTU_IRNEN) | BIT(clk->bits), GPTU_IRNEN); + gptu_w32(RUN_SEN | RUN_RL, GPTU_RUN(clk->bits)); + return 0; +} + +static void gptu_disable(struct clk *clk) +{ + gptu_w32(0, GPTU_RUN(clk->bits)); + gptu_w32(0, GPTU_CON(clk->bits)); + gptu_w32(0, GPTU_RLD(clk->bits)); + gptu_w32(gptu_r32(GPTU_IRNEN) & ~BIT(clk->bits), GPTU_IRNEN); + free_irq(irqres[clk->bits].start, NULL); +} + +static inline void clkdev_add_gptu(struct device *dev, const char *con, + unsigned int timer) +{ + struct clk *clk = kzalloc(sizeof(struct clk), GFP_KERNEL); + + if (!clk) + return; + clk->cl.dev_id = dev_name(dev); + clk->cl.con_id = con; + clk->cl.clk = clk; + clk->enable = gptu_enable; + clk->disable = gptu_disable; + clk->bits = timer; + clkdev_add(&clk->cl); +} + +static int gptu_probe(struct platform_device *pdev) +{ + struct clk *clk; + + if (of_irq_to_resource_table(pdev->dev.of_node, irqres, 6) != 6) { + dev_err(&pdev->dev, "Failed to get IRQ list\n"); + return -EINVAL; + } + + /* remap gptu register range */ + gptu_membase = devm_platform_get_and_ioremap_resource(pdev, 0, NULL); + if (IS_ERR(gptu_membase)) + return PTR_ERR(gptu_membase); + + /* enable our clock */ + clk = clk_get(&pdev->dev, NULL); + if (IS_ERR(clk)) { + dev_err(&pdev->dev, "Failed to get clock\n"); + return -ENOENT; + } + clk_enable(clk); + + /* power up the core */ + gptu_hwinit(); + + /* the gptu has a ID register */ + if (((gptu_r32(GPTU_ID) >> 8) & 0xff) != GPTU_MAGIC) { + dev_err(&pdev->dev, "Failed to find magic\n"); + gptu_hwexit(); + clk_disable(clk); + clk_put(clk); + return -ENAVAIL; + } + + /* register the clocks */ + clkdev_add_gptu(&pdev->dev, "timer1a", TIMER1A); + clkdev_add_gptu(&pdev->dev, "timer1b", TIMER1B); + clkdev_add_gptu(&pdev->dev, "timer2a", TIMER2A); + clkdev_add_gptu(&pdev->dev, "timer2b", TIMER2B); + clkdev_add_gptu(&pdev->dev, "timer3a", TIMER3A); + clkdev_add_gptu(&pdev->dev, "timer3b", TIMER3B); + + dev_info(&pdev->dev, "gptu: 6 timers loaded\n"); + + return 0; +} + +static const struct of_device_id gptu_match[] = { + { .compatible = "lantiq,gptu-xway" }, + {}, +}; + +static struct platform_driver dma_driver = { + .probe = gptu_probe, + .driver = { + .name = "gptu-xway", + .of_match_table = gptu_match, + }, +}; + +int __init gptu_init(void) +{ + int ret = platform_driver_register(&dma_driver); + + if (ret) + pr_info("gptu: Error registering platform driver\n"); + return ret; +} + +arch_initcall(gptu_init); |