Hi Mugunthan,
On Thu, Dec 24, 2015 at 6:38 PM, Mugunthan V N mugunthanvnm@ti.com wrote:
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 | 42 ++++++++++++++++++++++++++++++++++++ lib/time.c | 13 ++--------- 3 files changed, 87 insertions(+), 11 deletions(-) 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..bf9a30a --- /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@f00";};timer2@f00 {compatible = "vendor,some-timer";reg = <0xf00 0x10>;};+}; diff --git a/drivers/timer/timer-uclass.c b/drivers/timer/timer-uclass.c index aca421b..db43611 100644 --- a/drivers/timer/timer-uclass.c +++ b/drivers/timer/timer-uclass.c @@ -6,6 +6,8 @@
#include <common.h> #include <dm.h> +#include <dm/lists.h> +#include <dm/device-internal.h> #include <errno.h> #include <timer.h>
@@ -56,6 +58,46 @@ u64 timer_conv_64(u32 count) return ((u64)gd->timebase_h << 32) | gd->timebase_l; }
+int timer_init(void) +{
const void *blob = gd->fdt_blob;struct udevice *dev;int node;int ret;/* Check for a chosen timer to be used for tick */node = fdtdec_get_chosen_node(blob, "tick-timer");if (node < 0)return -ENODEV;
This changes now require every device tree provide a "tick-timer" under /chosen, which break all the existing dm timer enabled boards, and is not necessary.
We should do:
if (node < 0) { ret = uclass_first_device(UCLASS_TIMER, &dev); if (ret) return ret; if (!dev) return -ENODEV; gd->timer = dev; } else { .... }
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;}}if (dev) {gd->timer = dev;return 0;}ret = uclass_first_device(UCLASS_TIMER, &dev);if (ret)return ret;if (!dev)return -ENODEV;gd->timer = dev;return 0;+}
UCLASS_DRIVER(timer) = { .id = UCLASS_TIMER, .name = "timer", diff --git a/lib/time.c b/lib/time.c index f37a662..d4060f1 100644 --- a/lib/time.c +++ b/lib/time.c @@ -43,17 +43,8 @@ extern unsigned long __weak timer_read_counter(void); #ifdef CONFIG_TIMER static int notrace dm_timer_init(void) {
struct udevice *dev;int ret;if (!gd->timer) {ret = uclass_first_device(UCLASS_TIMER, &dev);if (ret)return ret;if (!dev)return -ENODEV;gd->timer = dev;}
if (!gd->timer)return timer_init();
Looks timer_init() is only called in timer-uclass.c, should we declare it as static? Otherwise timer_init() will be called in either board_f.c or board_r.c on different architectures. This causes timer devices to be probed twice. We may just simply move all codes in timer_init() into dm_timer_init().
return 0;}
Regards, Bin