Adding timer_init function to create and initialize the timer device on platforms where u-boot,dm-pre-reloc is not used. Since there will be multiple timer devices in the system, adding a tick-timer node in chosen node to know which timer device to be used as tick timer in u-boot.
Signed-off-by: Mugunthan V N mugunthanvnm@ti.com --- doc/device-tree-bindings/chosen.txt | 43 +++++++++++++++++++++++++++++++++++++ drivers/timer/timer-uclass.c | 34 +++++++++++++++++++++++++++++ lib/time.c | 5 +++++ 3 files changed, 82 insertions(+) create mode 100644 doc/device-tree-bindings/chosen.txt
diff --git a/doc/device-tree-bindings/chosen.txt b/doc/device-tree-bindings/chosen.txt new file mode 100644 index 0000000..58f29f9 --- /dev/null +++ b/doc/device-tree-bindings/chosen.txt @@ -0,0 +1,43 @@ +The chosen node +--------------- +The chosen node does not represent a real device, but serves as a place +for passing data like which serial device to used to print the logs etc + + +stdout-path property +-------------------- +Device trees may specify the device to be used for boot console output +with a stdout-path property under /chosen. + +Example +------- +/ { + chosen { + stdout-path = "/serial@f00:115200"; + }; + + serial@f00 { + compatible = "vendor,some-uart"; + reg = <0xf00 0x10>; + }; +}; + +tick-timer property +------------------- +In a system there are multiple timers, specify which timer to be used +as the tick-timer. Earlier it was hardcoded in the timer driver now +since device tree has all the timer nodes. Specify which timer to be +used as tick timer. + +Example +------- +/ { + chosen { + tick-timer = &timer2; + }; + + timer2@f00 { + compatible = "vendor,some-uart"; + reg = <0xf00 0x10>; + }; +}; diff --git a/drivers/timer/timer-uclass.c b/drivers/timer/timer-uclass.c index 12aee5b..78ec989 100644 --- a/drivers/timer/timer-uclass.c +++ b/drivers/timer/timer-uclass.c @@ -6,9 +6,13 @@
#include <common.h> #include <dm.h> +#include <dm/lists.h> +#include <dm/device-internal.h> #include <errno.h> #include <timer.h>
+DECLARE_GLOBAL_DATA_PTR; + /* * Implement a Timer uclass to work with lib/time.c. The timer is usually * a 32 bits free-running up counter. The get_rate() method is used to get @@ -35,6 +39,36 @@ unsigned long timer_get_rate(struct udevice *dev) return uc_priv->clock_rate; }
+int timer_init(void) +{ + const void *blob = gd->fdt_blob; + struct udevice *dev; + int node; + + if (CONFIG_IS_ENABLED(OF_CONTROL) && blob) { + /* Check for a chosen timer to be used for tick */ + node = fdtdec_get_chosen_node(blob, "tick-timer"); + if (node < 0) + return -ENODEV; + + if (uclass_get_device_by_of_offset(UCLASS_TIMER, node, &dev)) { + /* + * If the timer is not marked to be bound before + * relocation, bind it anyway. + */ + if (node > 0 && + !lists_bind_fdt(gd->dm_root, blob, node, &dev)) { + int ret = device_probe(dev); + if (ret) + return ret; + } + } + } + + gd->timer = dev; + return 0; +} + UCLASS_DRIVER(timer) = { .id = UCLASS_TIMER, .name = "timer", diff --git a/lib/time.c b/lib/time.c index b001745..22f7d23 100644 --- a/lib/time.c +++ b/lib/time.c @@ -47,6 +47,11 @@ static int notrace dm_timer_init(void) int ret;
if (!gd->timer) { + /* Check if we have a chosen timer */ + timer_init(); + if (gd->timer) + return 0; + ret = uclass_first_device(UCLASS_TIMER, &dev); if (ret) return ret;