Subject: [PATCH v10 15/21] ARM64 / ACPI: Introduce ACPI_IRQ_MODEL_GIC and register device's gsi

From: [email-masked] (Hanjun Guo)
Date: Fri, 20 Mar 2015 21:07:12 +0800

On 2015/3/20 3:37, Will Deacon wrote:
> On Thu, Mar 19, 2015 at 10:12:05AM +0000, Lorenzo Pieralisi wrote:
>> On Thu, Mar 19, 2015 at 03:45:35AM +0000, Hanjun Guo wrote:
>>>>> +	if (trigger == ACPI_EDGE_SENSITIVE &&
>>>>> +				polarity == ACPI_ACTIVE_LOW)
>>>>> +		irq_type = IRQ_TYPE_EDGE_FALLING;
>>>>> +	else if (trigger == ACPI_EDGE_SENSITIVE &&
>>>>> +				polarity == ACPI_ACTIVE_HIGH)
>>>>> +		irq_type = IRQ_TYPE_EDGE_RISING;
>>>>> +	else if (trigger == ACPI_LEVEL_SENSITIVE &&
>>>>> +				polarity == ACPI_ACTIVE_LOW)
>>>>> +		irq_type = IRQ_TYPE_LEVEL_LOW;
>>>>> +	else if (trigger == ACPI_LEVEL_SENSITIVE &&
>>>>> +				polarity == ACPI_ACTIVE_HIGH)
>>>>> +		irq_type = IRQ_TYPE_LEVEL_HIGH;
>>>>> +	else
>>>>> +		irq_type = IRQ_TYPE_NONE;
>>>>> +
>>>>> +	/*
>>>>> +	 * Since only one GIC is supported in ACPI 5.0, we can
>>>>> +	 * create mapping refer to the default domain
>>>>> +	 */
>>>>> +	irq = irq_create_mapping(NULL, gsi);
>>>>> +	if (!irq)
>>>>> +		return irq;
>>>>> +
>>>>> +	/* Set irq type if specified and different than the current one */
>>>>> +	if (irq_type != IRQ_TYPE_NONE &&
>>>>> +		irq_type != irq_get_trigger_type(irq))
>>>>> +		irq_set_irq_type(irq, irq_type);
>>>>> +	return irq;
>>>>> +}
>>>>> +EXPORT_SYMBOL_GPL(acpi_register_gsi);
>>>> I see you've still got this buried in the arch code. Is there any plan to
>>>> move it out, as I moaned about this in the last version of the series and
>>>> nothing seems to have changed?
>>> Ah, sorry. Last time when I was in Hongkong for LCA this Feb, I
>>> discussed with Lorenzo and he had a look into that too, he also met some
>>> obstacles to do that, so Lorenzo said that he will talk to you about
>>> this (Lorenzo, correct me if I'm wrong due to hearing problems of much
>>> noise in that room where we were talking).
>>>
>>> Anyway, if we move those functions to core code, such as irqdomain code,
>>> which will be compiled for x86 too, we can only set those functions as
>>> _weak, or we guard with them as #ifdef CONFIG_ARM64 ... #endif, so for
>>> me, it's really not a big deal to move those code out of arch/arm64, but
>>> I'm still open for suggestions if you can do that in a proper way.
>> You heard me clear and sound in HK, Will has a point and I looked into
>> this. Code is generic but not enough to be useful on other arches at
>> the moment, I need more time to look into this and see if we can move
>> this code to acpi core in a way that makes sense, to have, as you say,
>> a "default" implementation.
> Yeah, just something guarded by a CONFIG option (probably not ARM64
> though) would be enough, I think. Nothing too fancy.
Hi Will,

It is ARM64 related code and ACPI specific, I can come up with following code:

 arch/arm64/kernel/acpi.c | 67 ---------------------------------------------
 kernel/irq/irqdomain.c   | 70 ++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 70 insertions(+), 67 deletions(-)

diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
index 5819ef7..d207544 100644
--- a/arch/arm64/kernel/acpi.c
+++ b/arch/arm64/kernel/acpi.c
@@ -224,73 +224,6 @@ void __init acpi_init_cpus(void)
     pr_info("%d CPUs enabled, %d CPUs total\n", enabled_cpus, total_cpus);
 }
 
-int acpi_gsi_to_irq(u32 gsi, unsigned int *irq)
-{
-    *irq = irq_find_mapping(NULL, gsi);
-
-    return 0;
-}
-EXPORT_SYMBOL_GPL(acpi_gsi_to_irq);
-
-/*
- * success: return IRQ number (>0)
- * failure: return =< 0
- */
-int acpi_register_gsi(struct device *dev, u32 gsi, int trigger, int polarity)
-{
-    unsigned int irq;
-    unsigned int irq_type;
-
-    /*
-     * ACPI have no bindings to indicate SPI or PPI, so we
-     * use different mappings from DT in ACPI.
-     *
-     * For FDT
-     * PPI interrupt: in the range [0, 15];
-     * SPI interrupt: in the range [0, 987];
-     *
-     * For ACPI, GSI should be unique so using
-     * the hwirq directly for the mapping:
-     * PPI interrupt: in the range [16, 31];
-     * SPI interrupt: in the range [32, 1019];
-     */
-
-    if (trigger == ACPI_EDGE_SENSITIVE &&
-                polarity == ACPI_ACTIVE_LOW)
-        irq_type = IRQ_TYPE_EDGE_FALLING;
-    else if (trigger == ACPI_EDGE_SENSITIVE &&
-                polarity == ACPI_ACTIVE_HIGH)
-        irq_type = IRQ_TYPE_EDGE_RISING;
-    else if (trigger == ACPI_LEVEL_SENSITIVE &&
-                polarity == ACPI_ACTIVE_LOW)
-        irq_type = IRQ_TYPE_LEVEL_LOW;
-    else if (trigger == ACPI_LEVEL_SENSITIVE &&
-                polarity == ACPI_ACTIVE_HIGH)
-        irq_type = IRQ_TYPE_LEVEL_HIGH;
-    else
-        irq_type = IRQ_TYPE_NONE;
-
-    /*
-     * Since only one GIC is supported in ACPI 5.0, we can
-     * create mapping refer to the default domain
-     */
-    irq = irq_create_mapping(NULL, gsi);
-    if (!irq)
-        return irq;
-
-    /* Set irq type if specified and different than the current one */
-    if (irq_type != IRQ_TYPE_NONE &&
-        irq_type != irq_get_trigger_type(irq))
-        irq_set_irq_type(irq, irq_type);
-    return irq;
-}
-EXPORT_SYMBOL_GPL(acpi_register_gsi);
-
-void acpi_unregister_gsi(u32 gsi)
-{
-}
-EXPORT_SYMBOL_GPL(acpi_unregister_gsi);
-
 static int __init acpi_parse_fadt(struct acpi_table_header *table)
 {
     struct acpi_table_fadt *fadt = (struct acpi_table_fadt *)table;
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 7fac311..5a614bc 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -1,5 +1,6 @@
 #define pr_fmt(fmt)  "irq: " fmt
 
+#include <linux/acpi.h>
 #include <linux/debugfs.h>
 #include <linux/hardirq.h>
 #include <linux/interrupt.h>
@@ -568,6 +569,75 @@ unsigned int irq_find_mapping(struct irq_domain *domain,
 }
 EXPORT_SYMBOL_GPL(irq_find_mapping);
 
+#if defined(CONFIG_ARM64) && defined(CONFIG_ACPI)
+int acpi_gsi_to_irq(u32 gsi, unsigned int *irq)
+{
+    *irq = irq_find_mapping(NULL, gsi);
+
+    return 0;
+}
+EXPORT_SYMBOL_GPL(acpi_gsi_to_irq);
+
+/*
+ * success: return IRQ number (>0)
+ * failure: return =< 0
+ */
+int acpi_register_gsi(struct device *dev, u32 gsi, int trigger, int polarity)
+{
+    unsigned int irq;
+    unsigned int irq_type;
+
+    /*
+     * ACPI have no bindings to indicate SPI or PPI, so we
+     * use different mappings from DT in ACPI.
+     *
+     * For FDT
+     * PPI interrupt: in the range [0, 15];
+     * SPI interrupt: in the range [0, 987];
+     *
+     * For ACPI, GSI should be unique so using
+     * the hwirq directly for the mapping:
+     * PPI interrupt: in the range [16, 31];
+     * SPI interrupt: in the range [32, 1019];
+     */
+
+    if (trigger == ACPI_EDGE_SENSITIVE &&
+                polarity == ACPI_ACTIVE_LOW)
+        irq_type = IRQ_TYPE_EDGE_FALLING;
+    else if (trigger == ACPI_EDGE_SENSITIVE &&
+                polarity == ACPI_ACTIVE_HIGH)
+        irq_type = IRQ_TYPE_EDGE_RISING;
+    else if (trigger == ACPI_LEVEL_SENSITIVE &&
+                polarity == ACPI_ACTIVE_LOW)
+        irq_type = IRQ_TYPE_LEVEL_LOW;
+    else if (trigger == ACPI_LEVEL_SENSITIVE &&
+                polarity == ACPI_ACTIVE_HIGH)
+        irq_type = IRQ_TYPE_LEVEL_HIGH;
+    else
+        irq_type = IRQ_TYPE_NONE;
+
+    /*
+     * Since only one GIC is supported in ACPI 5.1, we can
+     * create mapping refer to the default domain
+     */
+    irq = irq_create_mapping(NULL, gsi);
+    if (!irq)
+        return irq;
+
+    /* Set irq type if specified and different than the current one */
+    if (irq_type != IRQ_TYPE_NONE &&
+        irq_type != irq_get_trigger_type(irq))
+        irq_set_irq_type(irq, irq_type);
+    return irq;
+}
+EXPORT_SYMBOL_GPL(acpi_register_gsi);
+
+void acpi_unregister_gsi(u32 gsi)
+{
+}
+EXPORT_SYMBOL_GPL(acpi_unregister_gsi);
+#endif    /* CONFIG_ARM64 && CONFIG_ACPI */
+
 #ifdef CONFIG_IRQ_DOMAIN_DEBUG
 static int virq_debug_show(struct seq_file *m, void *private)
 {

is this the way you prefered?

Thanks
Hanjun