Re: [Linaro-acpi] [PATCH non-pretimeout 5/7] ACPI: add GTDT table parse driver into ACPI driver

Hi Rafael,

Any comments on patch 5,6,7/7 of this patch set?

Thanks Hanjun

On 06/11/2015 01:47 AM, fu.wei@linaro.org wrote:

From: Fu Wei fu.wei@linaro.org

This driver adds support for parsing 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 fu.wei@linaro.org Signed-off-by: Hanjun Guo hanjun.guo@linaro.org

---

drivers/acpi/Kconfig | 9 ++++ drivers/acpi/Makefile | 1 + drivers/acpi/gtdt.c | 137 ++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 147 insertions(+) create mode 100644 drivers/acpi/gtdt.c

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index 1bbaa3d..e125698 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -433,4 +433,13 @@ config XPOWER_PMIC_OPREGION

endif

+config ACPI_GTDT

• bool "ACPI GTDT Support"
• depends on ARM64
• help

•  GTDT (Generic Timer Description Table) provides information
  

•  for per-processor timers and Platform (memory-mapped) timers
  

•  for ARM platforms. Select this option to provide information
  

•  needed for the timers init.
  

• endif # ACPI

diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile index 431e587..2c5a194 100644 --- a/drivers/acpi/Makefile +++ b/drivers/acpi/Makefile @@ -96,3 +96,4 @@ obj-$(CONFIG_ACPI_EXTLOG) += acpi_extlog.o obj-$(CONFIG_PMIC_OPREGION) += pmic/intel_pmic.o obj-$(CONFIG_CRC_PMIC_OPREGION) += pmic/intel_pmic_crc.o obj-$(CONFIG_XPOWER_PMIC_OPREGION) += pmic/intel_pmic_xpower.o +obj-$(CONFIG_ACPI_GTDT) += gtdt.o diff --git a/drivers/acpi/gtdt.c b/drivers/acpi/gtdt.c new file mode 100644 index 0000000..a92abf2 --- /dev/null +++ b/drivers/acpi/gtdt.c @@ -0,0 +1,137 @@ +/*

• • ARM Specific GTDT table Support
• • Copyright (C) 2015, Linaro Ltd.
• • Author: Fu Wei fu.wei@linaro.org

• •     Hanjun Guo <hanjun.guo@linaro.org>
    

• • This program is free software; you can redistribute it and/or modify
• • it under the terms of the GNU General Public License version 2 as
• • published by the Free Software Foundation.
• */

+#include <linux/acpi.h> +#include <linux/device.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h>

+static int __init map_generic_timer_interrupt(u32 interrupt, u32 flags) +{

• int trigger, polarity;
• if (!interrupt)

• return 0;
  

• trigger = (flags & ACPI_GTDT_INTERRUPT_MODE) ? ACPI_EDGE_SENSITIVE

• 	: ACPI_LEVEL_SENSITIVE;
  

• polarity = (flags & ACPI_GTDT_INTERRUPT_POLARITY) ? ACPI_ACTIVE_LOW

• 	: ACPI_ACTIVE_HIGH;
  

• return acpi_register_gsi(NULL, interrupt, trigger, polarity);

+}

+/*

• • Initialize a SBSA generic Watchdog platform device info from GTDT
• • According to SBSA specification the size of refresh and control
• • frames of SBSA Generic Watchdog is SZ_4K(Offset 0x000 – 0xFFF).
• */

+static int __init gtdt_import_sbsa_gwdt(struct acpi_gtdt_watchdog *wd,

• 			int index)
  

+{

• struct platform_device *pdev;
• int irq = map_generic_timer_interrupt(wd->timer_interrupt,

• 			      wd->timer_flags);
  

• struct resource res[] = {

• DEFINE_RES_IRQ_NAMED(irq, "ws0"),
  

• DEFINE_RES_MEM_NAMED(wd->refresh_frame_address, SZ_4K,
  

• 		     "refresh"),
  

• DEFINE_RES_MEM_NAMED(wd->control_frame_address, SZ_4K,
  

• 		     "control"),
  

• };
• pr_debug("GTDT: a Watchdog GT(0x%llx/0x%llx gsi:%u flags:0x%x)\n",

•  wd->refresh_frame_address, wd->control_frame_address,
  

•  wd->timer_interrupt, wd->timer_flags);
  

• if (!(wd->refresh_frame_address &&

•      wd->control_frame_address &&
  

•      wd->timer_interrupt)) {
  

• pr_err("GTDT: failed geting the device info.\n");
  

• return -EINVAL;
  

• }
• if (irq < 0) {

• pr_err("GTDT: failed to register GSI of the Watchdog GT.\n");
  

• return -EINVAL;
  

• }
• /*

• * Add a platform device named "sbsa-gwdt" to match the platform driver.
  

• * "sbsa-gwdt": SBSA(Server Base System Architecture) Generic Watchdog
  

• * The platform driver (like drivers/watchdog/sbsa_gwdt.c)can get device
  

• * info below by matching this name.
  

• */
  

• pdev = platform_device_register_simple("sbsa-gwdt", index, res,

• 			       ARRAY_SIZE(res));
  

• if (IS_ERR(pdev)) {

• acpi_unregister_gsi(wd->timer_interrupt);
  

• return PTR_ERR(pdev);
  

• }
• return 0;

+}

+static int __init gtdt_platform_timer_parse(struct acpi_table_header *table) +{

• struct acpi_gtdt_header *header;
• struct acpi_table_gtdt *gtdt;
• void *gtdt_subtable;
• int i, gwdt_index;
• int ret = 0;
• if (table->revision < 2) {

• pr_warn("GTDT: Revision:%d doesn't support Platform Timers.\n",
  

• 	table->revision);
  

• return 0;
  

• }
• gtdt = container_of(table, struct acpi_table_gtdt, header);
• if (!gtdt->platform_timer_count) {

• pr_info("GTDT: No Platform Timer structures.\n");
  

• return 0;
  

• }
• gtdt_subtable = (void *)gtdt + gtdt->platform_timer_offset;
• for (i = 0, gwdt_index = 0; i < gtdt->platform_timer_count; i++) {

• if (gtdt_subtable > (void *)table + table->length) {
  

• 	pr_err("GTDT: subtable pointer overflows, bad table\n");
  

• 	return -EINVAL;
  

• }
  

• header = (struct acpi_gtdt_header *)gtdt_subtable;
  

• if (header->type == ACPI_GTDT_TYPE_WATCHDOG) {
  

• 	ret = gtdt_import_sbsa_gwdt(gtdt_subtable, gwdt_index);
  

• 	if (ret)
  

• 		pr_err("GTDT: failed to import subtable %d\n",
  

• 		       i);
  

• 	else
  

• 		gwdt_index++;
  

• }
  

• gtdt_subtable += header->length;
  

• }
• return ret;

+}

+static int __init gtdt_platform_timer_init(void) +{

• if (acpi_disabled)

• return 0;
  

• return acpi_table_parse(ACPI_SIG_GTDT, gtdt_platform_timer_parse);

+}

+device_initcall(gtdt_platform_timer_init);