+CC Catalin and Will
On 2015年05月21日 16:32, fu.wei@linaro.org wrote:
From: Fu Wei fu.wei@linaro.org
Parse SBSA Generic Watchdog Structure in GTDT table of ACPI, and create a platform device with that information. This platform device can be used by the ARM SBSA Generic Watchdog driver.
Signed-off-by: Fu Wei fu.wei@linaro.org
arch/arm64/kernel/acpi.c | 136 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 136 insertions(+)
diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c index 8b83955..1ed11fd 100644 --- a/arch/arm64/kernel/acpi.c +++ b/arch/arm64/kernel/acpi.c @@ -23,6 +23,7 @@ #include <linux/irqdomain.h> #include <linux/memblock.h> #include <linux/of_fdt.h> +#include <linux/platform_device.h> #include <linux/smp.h>
#include <asm/cputype.h> @@ -343,3 +344,138 @@ void __init acpi_gic_init(void)
early_acpi_os_unmap_memory((char *)table, tbl_size); }
+static int __init acpi_gtdt_import_sbsa_gwdt(struct acpi_gtdt_watchdog *wd,
int index)+{
- struct platform_device *pdev;
- struct resource *res;
- u32 gsi, flags;
- int irq, trigger, polarity;
- resource_size_t rf_base_phy, cf_base_phy;
- int err = -ENOMEM;
- /*
* Get SBSA Generic Watchdog info* from a Watchdog GT type structure in GTDT*/- rf_base_phy = (resource_size_t)wd->refresh_frame_address;
- cf_base_phy = (resource_size_t)wd->control_frame_address;
- gsi = wd->timer_interrupt;
- flags = wd->timer_flags;
- pr_info("GTDT: a Watchdog GT structure(0x%llx/0x%llx gsi:%u flags:0x%x)\n",
rf_base_phy, cf_base_phy, gsi, flags);
Can we use pr_debug here? I don't think those information worthy a pr_info.
- if (!(rf_base_phy && cf_base_phy && gsi)) {
pr_err("GTDT: failed geting the device info.\n");return -EINVAL;- }
- trigger = (flags & ACPI_GTDT_INTERRUPT_MODE) ? ACPI_EDGE_SENSITIVE
: ACPI_LEVEL_SENSITIVE;- polarity = (flags & ACPI_GTDT_INTERRUPT_POLARITY) ? ACPI_ACTIVE_LOW
: ACPI_ACTIVE_HIGH;
I see places to duplicate this, I will look into this to see we can form a function to handle it.
- irq = acpi_register_gsi(NULL, gsi, trigger, polarity);
- if (irq < 0) {
pr_err("GTDT: failed to register GSI of the Watchdog GT.\n");return -EINVAL;- }
- pdev = platform_device_alloc("sbsa-gwdt", index);
Please put a comment before this function to explain why we need a "sbsa-gwdt" name here.
- if (!pdev)
goto err_unregister_gsi;- res = kcalloc(3, sizeof(*res), GFP_KERNEL);
- if (!res)
goto err_device_put;- res[0].start = rf_base_phy;
- res[0].end = rf_base_phy + SZ_4K - 1;
- res[0].name = "refresh";
- res[0].flags = IORESOURCE_MEM;
- res[1].start = cf_base_phy;
- res[1].end = cf_base_phy + SZ_4K - 1;
So why SZ_4K? is it defined in SBSA spec? if so, please comment on it too.
- res[1].name = "control";
- res[1].flags = IORESOURCE_MEM;
- res[2].start = irq;
- res[2].end = res[2].start;
- res[2].name = "ws0";
- res[2].flags = IORESOURCE_IRQ;
- err = platform_device_add_resources(pdev, res, 3);
- if (err)
goto err_free_res;- err = platform_device_add(pdev);
- if (err)
goto err_free_res;- return 0;
+err_free_res:
- kfree(res);
+err_device_put:
- platform_device_put(pdev);
+err_unregister_gsi:
- acpi_unregister_gsi(gsi);
- return err;
+}
+/* Initialize SBSA generic Watchdog platform device info from GTDT */ +static int __init acpi_gtdt_sbsa_gwdt_init(struct acpi_table_header *table) +{
- struct acpi_table_gtdt *gtdt;
- struct acpi_gtdt_header *header;
- void *gtdt_subtable;
- int i, gwdt_index;
- int ret = 0;
- if (table->revision < 2) {
pr_info("GTDT: Revision:%d doesn't support Platform Timers.\n",table->revision);
pr_warn() would be good.
Thanks Hanjun