diff options
| -rw-r--r-- | Documentation/devicetree/bindings/timer/renesas,cmt.txt | 47 | ||||
| -rw-r--r-- | drivers/clocksource/sh_cmt.c | 66 |
2 files changed, 95 insertions, 18 deletions
diff --git a/Documentation/devicetree/bindings/timer/renesas,cmt.txt b/Documentation/devicetree/bindings/timer/renesas,cmt.txt new file mode 100644 index 000000000000..a17418b0ece3 --- /dev/null +++ b/Documentation/devicetree/bindings/timer/renesas,cmt.txt @@ -0,0 +1,47 @@ +* Renesas R-Car Compare Match Timer (CMT) + +The CMT is a multi-channel 16/32/48-bit timer/counter with configurable clock +inputs and programmable compare match. + +Channels share hardware resources but their counter and compare match value +are independent. A particular CMT instance can implement only a subset of the +channels supported by the CMT model. Channel indices represent the hardware +position of the channel in the CMT and don't match the channel numbers in the +datasheets. + +Required Properties: + + - compatible: must contain one of the following. + - "renesas,cmt-32" for the 32-bit CMT + (CMT0 on sh7372, sh73a0 and r8a7740) + - "renesas,cmt-32-fast" for the 32-bit CMT with fast clock support + (CMT[234] on sh7372, sh73a0 and r8a7740) + - "renesas,cmt-48" for the 48-bit CMT + (CMT1 on sh7372, sh73a0 and r8a7740) + - "renesas,cmt-48-gen2" for the second generation 48-bit CMT + (CMT[01] on r8a73a4, r8a7790 and r8a7791) + + - reg: base address and length of the registers block for the timer module. + - interrupts: interrupt-specifier for the timer, one per channel. + - clocks: a list of phandle + clock-specifier pairs, one for each entry + in clock-names. + - clock-names: must contain "fck" for the functional clock. + + - renesas,channels-mask: bitmask of the available channels. + + +Example: R8A7790 (R-Car H2) CMT0 node + + CMT0 on R8A7790 implements hardware channels 5 and 6 only and names + them channels 0 and 1 in the documentation. + + cmt0: timer@ffca0000 { + compatible = "renesas,cmt-48-gen2"; + reg = <0 0xffca0000 0 0x1004>; + interrupts = <0 142 IRQ_TYPE_LEVEL_HIGH>, + <0 142 IRQ_TYPE_LEVEL_HIGH>; + clocks = <&mstp1_clks R8A7790_CLK_CMT0>; + clock-names = "fck"; + + renesas,channels-mask = <0x60>; + }; diff --git a/drivers/clocksource/sh_cmt.c b/drivers/clocksource/sh_cmt.c index 190c655d8352..2bd13b53b727 100644 --- a/drivers/clocksource/sh_cmt.c +++ b/drivers/clocksource/sh_cmt.c @@ -24,6 +24,7 @@ #include <linux/ioport.h> #include <linux/irq.h> #include <linux/module.h> +#include <linux/of.h> #include <linux/platform_device.h> #include <linux/pm_domain.h> #include <linux/pm_runtime.h> @@ -122,6 +123,7 @@ struct sh_cmt_device { struct sh_cmt_channel *channels; unsigned int num_channels; + unsigned int hw_channels; bool has_clockevent; bool has_clocksource; @@ -924,10 +926,35 @@ static int sh_cmt_map_memory(struct sh_cmt_device *cmt) return 0; } +static const struct platform_device_id sh_cmt_id_table[] = { + { "sh-cmt-16", (kernel_ulong_t)&sh_cmt_info[SH_CMT_16BIT] }, + { "sh-cmt-32", (kernel_ulong_t)&sh_cmt_info[SH_CMT_32BIT] }, + { "sh-cmt-32-fast", (kernel_ulong_t)&sh_cmt_info[SH_CMT_32BIT_FAST] }, + { "sh-cmt-48", (kernel_ulong_t)&sh_cmt_info[SH_CMT_48BIT] }, + { "sh-cmt-48-gen2", (kernel_ulong_t)&sh_cmt_info[SH_CMT_48BIT_GEN2] }, + { } +}; +MODULE_DEVICE_TABLE(platform, sh_cmt_id_table); + +static const struct of_device_id sh_cmt_of_table[] __maybe_unused = { + { .compatible = "renesas,cmt-32", .data = &sh_cmt_info[SH_CMT_32BIT] }, + { .compatible = "renesas,cmt-32-fast", .data = &sh_cmt_info[SH_CMT_32BIT_FAST] }, + { .compatible = "renesas,cmt-48", .data = &sh_cmt_info[SH_CMT_48BIT] }, + { .compatible = "renesas,cmt-48-gen2", .data = &sh_cmt_info[SH_CMT_48BIT_GEN2] }, + { } +}; +MODULE_DEVICE_TABLE(of, sh_cmt_of_table); + +static int sh_cmt_parse_dt(struct sh_cmt_device *cmt) +{ + struct device_node *np = cmt->pdev->dev.of_node; + + return of_property_read_u32(np, "renesas,channels-mask", + &cmt->hw_channels); +} + static int sh_cmt_setup(struct sh_cmt_device *cmt, struct platform_device *pdev) { - struct sh_timer_config *cfg = pdev->dev.platform_data; - const struct platform_device_id *id = pdev->id_entry; unsigned int mask; unsigned int i; int ret; @@ -936,13 +963,26 @@ static int sh_cmt_setup(struct sh_cmt_device *cmt, struct platform_device *pdev) cmt->pdev = pdev; raw_spin_lock_init(&cmt->lock); - if (!cfg) { + if (IS_ENABLED(CONFIG_OF) && pdev->dev.of_node) { + const struct of_device_id *id; + + id = of_match_node(sh_cmt_of_table, pdev->dev.of_node); + cmt->info = id->data; + + ret = sh_cmt_parse_dt(cmt); + if (ret < 0) + return ret; + } else if (pdev->dev.platform_data) { + struct sh_timer_config *cfg = pdev->dev.platform_data; + const struct platform_device_id *id = pdev->id_entry; + + cmt->info = (const struct sh_cmt_info *)id->driver_data; + cmt->hw_channels = cfg->channels_mask; + } else { dev_err(&cmt->pdev->dev, "missing platform data\n"); return -ENXIO; } - cmt->info = (const struct sh_cmt_info *)id->driver_data; - /* Get hold of clock. */ cmt->clk = clk_get(&cmt->pdev->dev, "fck"); if (IS_ERR(cmt->clk)) { @@ -960,8 +1000,7 @@ static int sh_cmt_setup(struct sh_cmt_device *cmt, struct platform_device *pdev) goto err_clk_unprepare; /* Allocate and setup the channels. */ - cmt->num_channels = hweight8(cfg->channels_mask); - + cmt->num_channels = hweight8(cmt->hw_channels); cmt->channels = kzalloc(cmt->num_channels * sizeof(*cmt->channels), GFP_KERNEL); if (cmt->channels == NULL) { @@ -973,7 +1012,7 @@ static int sh_cmt_setup(struct sh_cmt_device *cmt, struct platform_device *pdev) * Use the first channel as a clock event device and the second channel * as a clock source. If only one channel is available use it for both. */ - for (i = 0, mask = cfg->channels_mask; i < cmt->num_channels; ++i) { + for (i = 0, mask = cmt->hw_channels; i < cmt->num_channels; ++i) { unsigned int hwidx = ffs(mask) - 1; bool clocksource = i == 1 || cmt->num_channels == 1; bool clockevent = i == 0; @@ -1042,21 +1081,12 @@ static int sh_cmt_remove(struct platform_device *pdev) return -EBUSY; /* cannot unregister clockevent and clocksource */ } -static const struct platform_device_id sh_cmt_id_table[] = { - { "sh-cmt-16", (kernel_ulong_t)&sh_cmt_info[SH_CMT_16BIT] }, - { "sh-cmt-32", (kernel_ulong_t)&sh_cmt_info[SH_CMT_32BIT] }, - { "sh-cmt-32-fast", (kernel_ulong_t)&sh_cmt_info[SH_CMT_32BIT_FAST] }, - { "sh-cmt-48", (kernel_ulong_t)&sh_cmt_info[SH_CMT_48BIT] }, - { "sh-cmt-48-gen2", (kernel_ulong_t)&sh_cmt_info[SH_CMT_48BIT_GEN2] }, - { } -}; -MODULE_DEVICE_TABLE(platform, sh_cmt_id_table); - static struct platform_driver sh_cmt_device_driver = { .probe = sh_cmt_probe, .remove = sh_cmt_remove, .driver = { .name = "sh_cmt", + .of_match_table = of_match_ptr(sh_cmt_of_table), }, .id_table = sh_cmt_id_table, }; |