[v4,17/21] arm/acpi: Parse GTDT to initialize timer
diff mbox

Message ID 1453540813-15764-18-git-send-email-zhaoshenglong@huawei.com
State New, archived
Headers show

Commit Message

Shannon Zhao Jan. 23, 2016, 9:20 a.m. UTC
From: Shannon Zhao <shannon.zhao@linaro.org>

Parse GTDT (Generic Timer Descriptor Table) to initialize timer. Using
the information presented by GTDT to initialize the arch timer (not
memory-mapped).

Signed-off-by: Parth Dixit <parth.dixit@linaro.org>
Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
---
V4: Factor dt parts
---
 xen/arch/arm/time.c | 82 ++++++++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 68 insertions(+), 14 deletions(-)

Comments

Stefano Stabellini Feb. 2, 2016, 5:45 p.m. UTC | #1
On Sat, 23 Jan 2016, Shannon Zhao wrote:
> From: Shannon Zhao <shannon.zhao@linaro.org>
> 
> Parse GTDT (Generic Timer Descriptor Table) to initialize timer. Using
> the information presented by GTDT to initialize the arch timer (not
> memory-mapped).
> 
> Signed-off-by: Parth Dixit <parth.dixit@linaro.org>
> Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
> ---
> V4: Factor dt parts
> ---
>  xen/arch/arm/time.c | 82 ++++++++++++++++++++++++++++++++++++++++++++---------
>  1 file changed, 68 insertions(+), 14 deletions(-)
> 
> diff --git a/xen/arch/arm/time.c b/xen/arch/arm/time.c
> index 73a1a3e..4261207 100644
> --- a/xen/arch/arm/time.c
> +++ b/xen/arch/arm/time.c
> @@ -29,6 +29,7 @@
>  #include <xen/time.h>
>  #include <xen/sched.h>
>  #include <xen/event.h>
> +#include <xen/acpi.h>
>  #include <asm/system.h>
>  #include <asm/time.h>
>  #include <asm/gic.h>
> @@ -65,8 +66,52 @@ unsigned int timer_get_irq(enum timer_ppi ppi)
>  
>  static __initdata struct dt_device_node *timer;
>  
> +#ifdef CONFIG_ACPI
> +static u32 __init acpi_get_timer_irq_type(u32 flags)
> +{
> +    return (flags & ACPI_GTDT_INTERRUPT_MODE) ? IRQ_TYPE_EDGE_BOTH
> +                                              : IRQ_TYPE_LEVEL_MASK;
> +}
> +
> +/* Initialize per-processor generic timer */
> +static int __init arch_timer_acpi_init(struct acpi_table_header *header)
> +{
> +    u32 irq_type;
> +    struct acpi_table_gtdt *gtdt;
> +
> +    gtdt = container_of(header, struct acpi_table_gtdt, header);
> +
> +    /* Initialize all the generic timer IRQ variable from GTDT table */
> +    irq_type = acpi_get_timer_irq_type(gtdt->non_secure_el1_flags);
> +    irq_set_type(gtdt->non_secure_el1_interrupt, irq_type);
> +    timer_irq[TIMER_PHYS_NONSECURE_PPI] = gtdt->non_secure_el1_interrupt;
> +
> +    irq_type = acpi_get_timer_irq_type(gtdt->secure_el1_flags);
> +    irq_set_type(gtdt->secure_el1_interrupt, irq_type);
> +    timer_irq[TIMER_PHYS_SECURE_PPI] = gtdt->secure_el1_interrupt;
> +
> +    irq_type = acpi_get_timer_irq_type(gtdt->virtual_timer_flags);
> +    irq_set_type(gtdt->virtual_timer_interrupt, irq_type);
> +    timer_irq[TIMER_VIRT_PPI] = gtdt->virtual_timer_interrupt;
> +
> +    irq_type = acpi_get_timer_irq_type(gtdt->non_secure_el2_flags);
> +    irq_set_type(gtdt->non_secure_el2_interrupt, irq_type);
> +    timer_irq[TIMER_HYP_PPI] = gtdt->non_secure_el2_interrupt;
> +
> +    return 0;
> +}
> +
> +static void __init preinit_acpi_xen_time(void)
> +{
> +    acpi_table_parse(ACPI_SIG_GTDT, arch_timer_acpi_init);
> +    cpu_khz = READ_SYSREG32(CNTFRQ_EL0) / 1000;

I would move this and the other line like this in preinit_dt_xen_time to
preinit_xen_time, with a if (!cpu_khz) check.


> +}
> +#else
> +static inline void preinit_acpi_xen_time(void) { }
> +#endif

As usual, this can go away.

Everything else is good.


>  /* Set up the timer on the boot CPU (early init function) */
> -void __init preinit_xen_time(void)
> +static void __init preinit_dt_xen_time(void)
>  {
>      static const struct dt_device_match timer_ids[] __initconst =
>      {
> @@ -75,6 +120,7 @@ void __init preinit_xen_time(void)
>      };
>      int res;
>      u32 rate;
> +    unsigned int i;
>  
>      timer = dt_find_matching_node(NULL, timer_ids);
>      if ( !timer )
> @@ -82,10 +128,6 @@ void __init preinit_xen_time(void)
>  
>      dt_device_set_used_by(timer, DOMID_XEN);
>  
> -    res = platform_init_time();
> -    if ( res )
> -        panic("Timer: Cannot initialize platform timer");
> -
>      res = dt_property_read_u32(timer, "clock-frequency", &rate);
>      if ( res )
>      {
> @@ -95,15 +137,6 @@ void __init preinit_xen_time(void)
>      else
>          cpu_khz = READ_SYSREG32(CNTFRQ_EL0) / 1000;
>  
> -    boot_count = READ_SYSREG64(CNTPCT_EL0);
> -}
> -
> -/* Set up the timer on the boot CPU (late init function) */
> -int __init init_xen_time(void)
> -{
> -    int res;
> -    unsigned int i;
> -
>      /* Retrieve all IRQs for the timer */
>      for ( i = TIMER_PHYS_SECURE_PPI; i < MAX_TIMER_PPI; i++ )
>      {
> @@ -113,7 +146,28 @@ int __init init_xen_time(void)
>              panic("Timer: Unable to retrieve IRQ %u from the device tree", i);
>          timer_irq[i] = res;
>      }
> +}
> +
> +void __init preinit_xen_time(void)
> +{
> +    int res;
>  
> +    /* Initialize all the generic timers presented in GTDT */
> +    if ( acpi_disabled )
> +        preinit_dt_xen_time();
> +    else
> +        preinit_acpi_xen_time();
> +
> +    res = platform_init_time();
> +    if ( res )
> +        panic("Timer: Cannot initialize platform timer");
> +
> +    boot_count = READ_SYSREG64(CNTPCT_EL0);
> +}
> +
> +/* Set up the timer on the boot CPU (late init function) */
> +int __init init_xen_time(void)
> +{
>      /* Check that this CPU supports the Generic Timer interface */
>      if ( !cpu_has_gentimer )
>          panic("CPU does not support the Generic Timer v1 interface");
> -- 
> 2.0.4
> 
>

Patch
diff mbox

diff --git a/xen/arch/arm/time.c b/xen/arch/arm/time.c
index 73a1a3e..4261207 100644
--- a/xen/arch/arm/time.c
+++ b/xen/arch/arm/time.c
@@ -29,6 +29,7 @@ 
 #include <xen/time.h>
 #include <xen/sched.h>
 #include <xen/event.h>
+#include <xen/acpi.h>
 #include <asm/system.h>
 #include <asm/time.h>
 #include <asm/gic.h>
@@ -65,8 +66,52 @@  unsigned int timer_get_irq(enum timer_ppi ppi)
 
 static __initdata struct dt_device_node *timer;
 
+#ifdef CONFIG_ACPI
+static u32 __init acpi_get_timer_irq_type(u32 flags)
+{
+    return (flags & ACPI_GTDT_INTERRUPT_MODE) ? IRQ_TYPE_EDGE_BOTH
+                                              : IRQ_TYPE_LEVEL_MASK;
+}
+
+/* Initialize per-processor generic timer */
+static int __init arch_timer_acpi_init(struct acpi_table_header *header)
+{
+    u32 irq_type;
+    struct acpi_table_gtdt *gtdt;
+
+    gtdt = container_of(header, struct acpi_table_gtdt, header);
+
+    /* Initialize all the generic timer IRQ variable from GTDT table */
+    irq_type = acpi_get_timer_irq_type(gtdt->non_secure_el1_flags);
+    irq_set_type(gtdt->non_secure_el1_interrupt, irq_type);
+    timer_irq[TIMER_PHYS_NONSECURE_PPI] = gtdt->non_secure_el1_interrupt;
+
+    irq_type = acpi_get_timer_irq_type(gtdt->secure_el1_flags);
+    irq_set_type(gtdt->secure_el1_interrupt, irq_type);
+    timer_irq[TIMER_PHYS_SECURE_PPI] = gtdt->secure_el1_interrupt;
+
+    irq_type = acpi_get_timer_irq_type(gtdt->virtual_timer_flags);
+    irq_set_type(gtdt->virtual_timer_interrupt, irq_type);
+    timer_irq[TIMER_VIRT_PPI] = gtdt->virtual_timer_interrupt;
+
+    irq_type = acpi_get_timer_irq_type(gtdt->non_secure_el2_flags);
+    irq_set_type(gtdt->non_secure_el2_interrupt, irq_type);
+    timer_irq[TIMER_HYP_PPI] = gtdt->non_secure_el2_interrupt;
+
+    return 0;
+}
+
+static void __init preinit_acpi_xen_time(void)
+{
+    acpi_table_parse(ACPI_SIG_GTDT, arch_timer_acpi_init);
+    cpu_khz = READ_SYSREG32(CNTFRQ_EL0) / 1000;
+}
+#else
+static inline void preinit_acpi_xen_time(void) { }
+#endif
+
 /* Set up the timer on the boot CPU (early init function) */
-void __init preinit_xen_time(void)
+static void __init preinit_dt_xen_time(void)
 {
     static const struct dt_device_match timer_ids[] __initconst =
     {
@@ -75,6 +120,7 @@  void __init preinit_xen_time(void)
     };
     int res;
     u32 rate;
+    unsigned int i;
 
     timer = dt_find_matching_node(NULL, timer_ids);
     if ( !timer )
@@ -82,10 +128,6 @@  void __init preinit_xen_time(void)
 
     dt_device_set_used_by(timer, DOMID_XEN);
 
-    res = platform_init_time();
-    if ( res )
-        panic("Timer: Cannot initialize platform timer");
-
     res = dt_property_read_u32(timer, "clock-frequency", &rate);
     if ( res )
     {
@@ -95,15 +137,6 @@  void __init preinit_xen_time(void)
     else
         cpu_khz = READ_SYSREG32(CNTFRQ_EL0) / 1000;
 
-    boot_count = READ_SYSREG64(CNTPCT_EL0);
-}
-
-/* Set up the timer on the boot CPU (late init function) */
-int __init init_xen_time(void)
-{
-    int res;
-    unsigned int i;
-
     /* Retrieve all IRQs for the timer */
     for ( i = TIMER_PHYS_SECURE_PPI; i < MAX_TIMER_PPI; i++ )
     {
@@ -113,7 +146,28 @@  int __init init_xen_time(void)
             panic("Timer: Unable to retrieve IRQ %u from the device tree", i);
         timer_irq[i] = res;
     }
+}
+
+void __init preinit_xen_time(void)
+{
+    int res;
 
+    /* Initialize all the generic timers presented in GTDT */
+    if ( acpi_disabled )
+        preinit_dt_xen_time();
+    else
+        preinit_acpi_xen_time();
+
+    res = platform_init_time();
+    if ( res )
+        panic("Timer: Cannot initialize platform timer");
+
+    boot_count = READ_SYSREG64(CNTPCT_EL0);
+}
+
+/* Set up the timer on the boot CPU (late init function) */
+int __init init_xen_time(void)
+{
     /* Check that this CPU supports the Generic Timer interface */
     if ( !cpu_has_gentimer )
         panic("CPU does not support the Generic Timer v1 interface");