acpi/arm64: Add SBSA Generic Watchdog support in GTDT driver
This driver adds support for parsing SBSA Generic Watchdog timer
in GTDT, parse all info in SBSA Generic Watchdog Structure in GTDT,
and creating a platform device with that information.
This allows the operating system to obtain device data from the
resource of platform device. The platform device named "sbsa-gwdt"
can be used by the ARM SBSA Generic Watchdog driver.
Signed-off-by: Fu Wei <email address hidden>
Signed-off-by: Hanjun Guo <email address hidden>
Tested-by: Xiongfeng Wang <email address hidden>
[v21 submittal]
acpi/arm64: Add memory-mapped timer support in GTDT driver
On platforms booting with ACPI, architected memory-mapped timers'
configuration data is provided by firmware through the ACPI GTDT
static table.
The clocksource architected timer kernel driver requires a firmware
interface to collect timer configuration and configure its driver.
this infrastructure is present for device tree systems, but it is
missing on systems booting with ACPI.
Implement the kernel infrastructure required to parse the static
ACPI GTDT table so that the architected timer clocksource driver can
make use of it on systems booting with ACPI, therefore enabling
the corresponding timers configuration.
clocksource: arm_arch_timer: simplify ACPI support code.
The patch update arm_arch_timer driver to use the function
provided by the new GTDT driver of ACPI.
By this way, arm_arch_timer.c can be simplified, and separate
all the ACPI GTDT knowledge from this timer driver.
This patch adds support for parsing arch timer info in GTDT,
provides some kernel APIs to parse all the PPIs and
always-on info in GTDT and export them.
By this driver, we can simplify arm_arch_timer drivers, and
separate the ACPI GTDT knowledge from it.
Signed-off-by: Fu Wei <email address hidden>
Signed-off-by: Hanjun Guo <email address hidden>
Acked-by: Rafael J. Wysocki <email address hidden>
Tested-by: Xiongfeng Wang <email address hidden>
Reviewed-by: Hanjun Guo <email address hidden>
Tested-by: Hanjun Guo <email address hidden>
[v21 submittal]
Currently the code to probe MMIO architected timers mixes DT parsing with
actual poking of hardware. This makes the code harder than necessary to
understand, and makes it difficult to add support for probing via ACPI.
This patch factors all the DT-specific logic out of arch_timer_mem_init(),
into a new function arch_timer_mem_of_init().
The former pokes the hardware and determines the suitablility of frames
based on a datastructure populated by the latter.
This cleanly separates the two and will make it possible to add probing
using the ACPI GTDT in subsequent patches.
clocksource: arm_arch_timer: move arch_timer_needs_of_probing into DT init call
Because arch_timer_needs_of_probing is only for booting with device-tree,
but arch_timer_common_init is a generic init call which shouldn't include
the FW-specific code. It's better to put arch_timer_needs_of_probing into
DT init function.
But for per-cpu timer, the arch_timer_common_init is called from
arch_timer_init. For reaching the goal above, this patch disassemble
arch_timer_init and use arch_timer_register and arch_timer_common_init
directly, just like arch_timer_mem init code is doing.
By this way, all the DT relevant code are only called from DT init call.
