GTDT (Generic Timer Description Table) contains information for arch timer initialization, this patch use this table to probe arm timer.

[Hanjun: modify the patch to use GTDT table presented in ACPI 5.0, and modify the change log]

Signed-off-by: Amit Daniel Kachhap amit.daniel@samsung.com Signed-off-by: Hanjun Guo hanjun.guo@linaro.org --- drivers/clocksource/arm_arch_timer.c | 129 ++++++++++++++++++++++++++++++---- include/clocksource/arm_arch_timer.h | 7 +- 2 files changed, 120 insertions(+), 16 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index fbd9ccd..4799347 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -19,6 +19,7 @@ #include <linux/of_address.h> #include <linux/io.h> #include <linux/slab.h> +#include <linux/acpi.h>

#include <asm/arch_timer.h> #include <asm/virt.h> @@ -579,20 +580,8 @@ static void __init arch_timer_common_init(void) arch_timer_arch_init(); }

-static void __init arch_timer_init(struct device_node *np) +static void __init arch_timer_init(void) { - int i; - - if (arch_timers_present & ARCH_CP15_TIMER) { - pr_warn("arch_timer: multiple nodes in dt, skipping\n"); - return; - } - - arch_timers_present |= ARCH_CP15_TIMER; - for (i = PHYS_SECURE_PPI; i < MAX_TIMER_PPI; i++) - arch_timer_ppi[i] = irq_of_parse_and_map(np, i); - arch_timer_detect_rate(NULL, np); - /* * If HYP mode is available, we know that the physical timer * has been configured to be accessible from PL1. Use it, so @@ -614,8 +603,118 @@ static void __init arch_timer_init(struct device_node *np) arch_timer_register(); arch_timer_common_init(); } -CLOCKSOURCE_OF_DECLARE(armv7_arch_timer, "arm,armv7-timer", arch_timer_init); -CLOCKSOURCE_OF_DECLARE(armv8_arch_timer, "arm,armv8-timer", arch_timer_init); + +static void __init arch_timer_of_init(struct device_node *np) +{ + int i; + + if (arch_timers_present & ARCH_CP15_TIMER) { + pr_warn("arch_timer: multiple nodes in dt, skipping\n"); + return; + } + + arch_timers_present |= ARCH_CP15_TIMER; + for (i = PHYS_SECURE_PPI; i < MAX_TIMER_PPI; i++) + arch_timer_ppi[i] = irq_of_parse_and_map(np, i); + arch_timer_detect_rate(NULL, np); + + arch_timer_init(); +} +CLOCKSOURCE_OF_DECLARE(armv7_arch_timer, "arm,armv7-timer", arch_timer_of_init); +CLOCKSOURCE_OF_DECLARE(armv8_arch_timer, "arm,armv8-timer", arch_timer_of_init); + +#ifdef CONFIG_ACPI +void __init arch_timer_acpi_init(void) +{ + struct acpi_table_gtdt *gtdt; + acpi_size tbl_size; + int trigger, polarity; + void __iomem *base = NULL; + + if (acpi_disabled) + return; + + if (arch_timers_present & ARCH_CP15_TIMER) { + pr_warn("arch_timer: already initialized, skipping\n"); + return; + } + + if (ACPI_FAILURE(acpi_get_table_with_size(ACPI_SIG_GTDT, 0, + (struct acpi_table_header **)&gtdt, &tbl_size))) { + pr_err("arch_timer: GTDT table not defined\n"); + return; + } + + arch_timers_present |= ARCH_CP15_TIMER; + + /* + * Get the timer frequency. Since there is no frequency info + * in the GTDT table, so we should read it from CNTFREG register + * or hard code here to wait for the new ACPI spec available. + */ + if (!gtdt->address) { + arch_timer_rate = arch_timer_get_cntfrq(); + } else { + base = ioremap(gtdt->address, CNTFRQ); + if (!base) { + pr_warn("arch_timer: unable to map arch timer base address\n"); + return; + } + + arch_timer_rate = readl_relaxed(base + CNTFRQ); + iounmap(base); + } + + if (!arch_timer_rate) { + /* Hard code here to set frequence ? */ + pr_warn("arch_timer: Could not get frequency from GTDT table or CNTFREG\n"); + } + + if (gtdt->secure_pl1_interrupt) { + trigger = (gtdt->secure_pl1_flags & ACPI_GTDT_INTERRUPT_MODE) ? + ACPI_EDGE_SENSITIVE : ACPI_LEVEL_SENSITIVE; + polarity = + (gtdt->secure_pl1_flags & ACPI_GTDT_INTERRUPT_POLARITY) + ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH; + arch_timer_ppi[0] = acpi_register_gsi(NULL, + gtdt->secure_pl1_interrupt, trigger, polarity); + } + if (gtdt->non_secure_pl1_interrupt) { + trigger = + (gtdt->non_secure_pl1_flags & ACPI_GTDT_INTERRUPT_MODE) + ? ACPI_EDGE_SENSITIVE : ACPI_LEVEL_SENSITIVE; + polarity = + (gtdt->non_secure_pl1_flags & ACPI_GTDT_INTERRUPT_POLARITY) + ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH; + arch_timer_ppi[1] = acpi_register_gsi(NULL, + gtdt->non_secure_pl1_interrupt, trigger, polarity); + } + if (gtdt->virtual_timer_interrupt) { + trigger = (gtdt->virtual_timer_flags & ACPI_GTDT_INTERRUPT_MODE) + ? ACPI_EDGE_SENSITIVE : ACPI_LEVEL_SENSITIVE; + polarity = + (gtdt->virtual_timer_flags & ACPI_GTDT_INTERRUPT_POLARITY) + ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH; + arch_timer_ppi[2] = acpi_register_gsi(NULL, + gtdt->virtual_timer_interrupt, trigger, polarity); + } + if (gtdt->non_secure_pl2_interrupt) { + trigger = + (gtdt->non_secure_pl2_flags & ACPI_GTDT_INTERRUPT_MODE) + ? ACPI_EDGE_SENSITIVE : ACPI_LEVEL_SENSITIVE; + polarity = + (gtdt->non_secure_pl2_flags & ACPI_GTDT_INTERRUPT_POLARITY) + ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH; + arch_timer_ppi[3] = acpi_register_gsi(NULL, + gtdt->non_secure_pl2_interrupt, trigger, polarity); + } + + early_acpi_os_unmap_memory(gtdt, tbl_size); + arch_timer_init(); +} +#else +void __init arch_timer_acpi_init(void) { return; }; +#endif

static void __init arch_timer_mem_init(struct device_node *np) { diff --git a/include/clocksource/arm_arch_timer.h b/include/clocksource/arm_arch_timer.h index 93b7f96..eeb9ce3 100644 --- a/include/clocksource/arm_arch_timer.h +++ b/include/clocksource/arm_arch_timer.h @@ -38,7 +38,7 @@ enum arch_timer_reg { extern u32 arch_timer_get_rate(void); extern u64 (*arch_timer_read_counter)(void); extern struct timecounter *arch_timer_get_timecounter(void); - +extern void __init arch_timer_acpi_init(void); #else

static inline u32 arch_timer_get_rate(void) @@ -56,6 +56,11 @@ static inline struct timecounter *arch_timer_get_timecounter(void) return NULL; }

+static inline void arch_timer_acpi_init(void) +{ + return; +} + #endif

#endif

Use arch_timer_acpi_init() on ARMv7.

Signed-off-by: Hanjun Guo hanjun.guo@linaro.org --- arch/arm/kernel/time.c | 4 ++++ 1 file changed, 4 insertions(+)

diff --git a/arch/arm/kernel/time.c b/arch/arm/kernel/time.c index 829a96d..14aac22 100644 --- a/arch/arm/kernel/time.c +++ b/arch/arm/kernel/time.c @@ -27,6 +27,8 @@ #include <linux/timex.h> #include <linux/timer.h>

+#include <clocksource/arm_arch_timer.h> + #include <asm/mach/arch.h> #include <asm/mach/time.h> #include <asm/stacktrace.h> @@ -124,5 +126,7 @@ void __init time_init(void) of_clk_init(NULL); #endif clocksource_of_init(); + if (!arch_timer_get_rate()) + arch_timer_acpi_init(); } }