ACPICA: Events: Introduce acpi_mask_gpe() to implement GPE masking mechanism
authorLv Zheng <lv.zheng@intel.com>
Thu, 4 Aug 2016 08:43:39 +0000 (16:43 +0800)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Sat, 13 Aug 2016 01:09:33 +0000 (03:09 +0200)
ACPICA commit 23a417ca406a527e7ae1710893e59a8b6db30e14

There is a facility in Linux, developers can control the enabling/disabling
of a GPE via /sys/firmware/acpi/interrupts/gpexx. This is mainly for
debugging purposes.

But many users expect to use this facility to implement quirks to mask a
specific GPE when there is a gap in Linux causing this GPE to flood. This
is not working correctly because currently this facility invokes
enabling/disabling counting based GPE driver APIs:
 acpi_enable_gpe()/acpi_disable_gpe()
and the GPE drivers can still affect the count to mess up the GPE
masking purposes.

However, most of the IRQ chip designs allow masking/unmasking IRQs via a
masking bit which is different from the enabled bit to achieve the same
purpose. But the GPE hardware doesn't contain such a feature, this brings
the trouble.

In this patch, we introduce a software mechanism to implement the GPE
masking feature, and acpi_mask_gpe() are provided to the OSPMs to
mask/unmask GPEs in the above mentioned situation instead of
acpi_enable_gpe()/acpi_disable_gpe(). ACPICA BZ 1102. Lv Zheng.

Link: https://github.com/acpica/acpica/commit/23a417ca
Link: https://bugs.acpica.org/show_bug.cgi?id=1102
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
drivers/acpi/acpica/acevents.h
drivers/acpi/acpica/aclocal.h
drivers/acpi/acpica/evgpe.c
drivers/acpi/acpica/evxfgpe.c
drivers/acpi/acpica/hwgpe.c
include/acpi/acpixf.h
include/acpi/actypes.h

index 77af91c..92fa47c 100644 (file)
@@ -85,6 +85,9 @@ acpi_ev_update_gpe_enable_mask(struct acpi_gpe_event_info *gpe_event_info);
 
 acpi_status acpi_ev_enable_gpe(struct acpi_gpe_event_info *gpe_event_info);
 
+acpi_status
+acpi_ev_mask_gpe(struct acpi_gpe_event_info *gpe_event_info, u8 is_masked);
+
 acpi_status
 acpi_ev_add_gpe_reference(struct acpi_gpe_event_info *gpe_event_info);
 
index 13331d7..dff1207 100644 (file)
@@ -484,6 +484,7 @@ struct acpi_gpe_event_info {
        u8 flags;               /* Misc info about this GPE */
        u8 gpe_number;          /* This GPE */
        u8 runtime_count;       /* References to a run GPE */
+       u8 disable_for_dispatch;        /* Masked during dispatching */
 };
 
 /* Information about a GPE register pair, one per each status/enable pair in an array */
@@ -494,6 +495,7 @@ struct acpi_gpe_register_info {
        u16 base_gpe_number;    /* Base GPE number for this register */
        u8 enable_for_wake;     /* GPEs to keep enabled when sleeping */
        u8 enable_for_run;      /* GPEs to keep enabled when running */
+       u8 mask_for_run;        /* GPEs to keep masked when running */
        u8 enable_mask;         /* Current mask of enabled GPEs */
 };
 
index 4b4949c..bdb10be 100644 (file)
@@ -128,6 +128,60 @@ acpi_status acpi_ev_enable_gpe(struct acpi_gpe_event_info *gpe_event_info)
        return_ACPI_STATUS(status);
 }
 
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ev_mask_gpe
+ *
+ * PARAMETERS:  gpe_event_info          - GPE to be blocked/unblocked
+ *              is_masked               - Whether the GPE is masked or not
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Unconditionally mask/unmask a GPE during runtime.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ev_mask_gpe(struct acpi_gpe_event_info *gpe_event_info, u8 is_masked)
+{
+       struct acpi_gpe_register_info *gpe_register_info;
+       u32 register_bit;
+
+       ACPI_FUNCTION_TRACE(ev_mask_gpe);
+
+       gpe_register_info = gpe_event_info->register_info;
+       if (!gpe_register_info) {
+               return_ACPI_STATUS(AE_NOT_EXIST);
+       }
+
+       register_bit = acpi_hw_get_gpe_register_bit(gpe_event_info);
+
+       /* Perform the action */
+
+       if (is_masked) {
+               if (register_bit & gpe_register_info->mask_for_run) {
+                       return_ACPI_STATUS(AE_BAD_PARAMETER);
+               }
+
+               (void)acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
+               ACPI_SET_BIT(gpe_register_info->mask_for_run, (u8)register_bit);
+       } else {
+               if (!(register_bit & gpe_register_info->mask_for_run)) {
+                       return_ACPI_STATUS(AE_BAD_PARAMETER);
+               }
+
+               ACPI_CLEAR_BIT(gpe_register_info->mask_for_run,
+                              (u8)register_bit);
+               if (gpe_event_info->runtime_count
+                   && !gpe_event_info->disable_for_dispatch) {
+                       (void)acpi_hw_low_set_gpe(gpe_event_info,
+                                                 ACPI_GPE_ENABLE);
+               }
+       }
+
+       return_ACPI_STATUS(AE_OK);
+}
+
 /*******************************************************************************
  *
  * FUNCTION:    acpi_ev_add_gpe_reference
@@ -674,6 +728,7 @@ acpi_status acpi_ev_finish_gpe(struct acpi_gpe_event_info *gpe_event_info)
         * in the event_info.
         */
        (void)acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_CONDITIONAL_ENABLE);
+       gpe_event_info->disable_for_dispatch = FALSE;
        return (AE_OK);
 }
 
@@ -737,6 +792,8 @@ acpi_ev_gpe_dispatch(struct acpi_namespace_node *gpe_device,
                }
        }
 
+       gpe_event_info->disable_for_dispatch = TRUE;
+
        /*
         * Dispatch the GPE to either an installed handler or the control
         * method associated with this GPE (_Lxx or _Exx). If a handler
index 17cfef7..d7a3b27 100644 (file)
@@ -235,11 +235,13 @@ acpi_status acpi_set_gpe(acpi_handle gpe_device, u32 gpe_number, u8 action)
        case ACPI_GPE_ENABLE:
 
                status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_ENABLE);
+               gpe_event_info->disable_for_dispatch = FALSE;
                break;
 
        case ACPI_GPE_DISABLE:
 
                status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
+               gpe_event_info->disable_for_dispatch = TRUE;
                break;
 
        default:
@@ -255,6 +257,47 @@ unlock_and_exit:
 
 ACPI_EXPORT_SYMBOL(acpi_set_gpe)
 
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_mask_gpe
+ *
+ * PARAMETERS:  gpe_device          - Parent GPE Device. NULL for GPE0/GPE1
+ *              gpe_number          - GPE level within the GPE block
+ *              is_masked           - Whether the GPE is masked or not
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Unconditionally mask/unmask the an individual GPE, ex., to
+ *              prevent a GPE flooding.
+ *
+ ******************************************************************************/
+acpi_status acpi_mask_gpe(acpi_handle gpe_device, u32 gpe_number, u8 is_masked)
+{
+       struct acpi_gpe_event_info *gpe_event_info;
+       acpi_status status;
+       acpi_cpu_flags flags;
+
+       ACPI_FUNCTION_TRACE(acpi_mask_gpe);
+
+       flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
+
+       /* Ensure that we have a valid GPE number */
+
+       gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
+       if (!gpe_event_info) {
+               status = AE_BAD_PARAMETER;
+               goto unlock_and_exit;
+       }
+
+       status = acpi_ev_mask_gpe(gpe_event_info, is_masked);
+
+unlock_and_exit:
+       acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
+       return_ACPI_STATUS(status);
+}
+
+ACPI_EXPORT_SYMBOL(acpi_mask_gpe)
+
 /*******************************************************************************
  *
  * FUNCTION:    acpi_mark_gpe_for_wake
index bdecd5e..76b0e35 100644 (file)
@@ -98,7 +98,7 @@ acpi_status
 acpi_hw_low_set_gpe(struct acpi_gpe_event_info *gpe_event_info, u32 action)
 {
        struct acpi_gpe_register_info *gpe_register_info;
-       acpi_status status;
+       acpi_status status = AE_OK;
        u32 enable_mask;
        u32 register_bit;
 
@@ -148,9 +148,14 @@ acpi_hw_low_set_gpe(struct acpi_gpe_event_info *gpe_event_info, u32 action)
                return (AE_BAD_PARAMETER);
        }
 
-       /* Write the updated enable mask */
+       if (!(register_bit & gpe_register_info->mask_for_run)) {
 
-       status = acpi_hw_write(enable_mask, &gpe_register_info->enable_address);
+               /* Write the updated enable mask */
+
+               status =
+                   acpi_hw_write(enable_mask,
+                                 &gpe_register_info->enable_address);
+       }
        return (status);
 }
 
@@ -242,6 +247,12 @@ acpi_hw_get_gpe_status(struct acpi_gpe_event_info *gpe_event_info,
                local_event_status |= ACPI_EVENT_FLAG_ENABLED;
        }
 
+       /* GPE currently masked? (masked for runtime?) */
+
+       if (register_bit & gpe_register_info->mask_for_run) {
+               local_event_status |= ACPI_EVENT_FLAG_MASKED;
+       }
+
        /* GPE enabled for wake? */
 
        if (register_bit & gpe_register_info->enable_for_wake) {
@@ -397,6 +408,7 @@ acpi_hw_enable_runtime_gpe_block(struct acpi_gpe_xrupt_info *gpe_xrupt_info,
        u32 i;
        acpi_status status;
        struct acpi_gpe_register_info *gpe_register_info;
+       u8 enable_mask;
 
        /* NOTE: assumes that all GPEs are currently disabled */
 
@@ -410,9 +422,10 @@ acpi_hw_enable_runtime_gpe_block(struct acpi_gpe_xrupt_info *gpe_xrupt_info,
 
                /* Enable all "runtime" GPEs in this register */
 
+               enable_mask = gpe_register_info->enable_for_run &
+                   ~gpe_register_info->mask_for_run;
                status =
-                   acpi_hw_gpe_enable_write(gpe_register_info->enable_for_run,
-                                            gpe_register_info);
+                   acpi_hw_gpe_enable_write(enable_mask, gpe_register_info);
                if (ACPI_FAILURE(status)) {
                        return (status);
                }
index 875964d..c2d4b9c 100644 (file)
@@ -735,6 +735,10 @@ ACPI_HW_DEPENDENT_RETURN_STATUS(acpi_status
                                acpi_finish_gpe(acpi_handle gpe_device,
                                                u32 gpe_number))
 
+ACPI_HW_DEPENDENT_RETURN_STATUS(acpi_status
+                               acpi_mask_gpe(acpi_handle gpe_device,
+                                             u32 gpe_number, u8 is_masked))
+
 ACPI_HW_DEPENDENT_RETURN_STATUS(acpi_status
                                acpi_mark_gpe_for_wake(acpi_handle gpe_device,
                                                       u32 gpe_number))
index cb389ef..fa4bd6a 100644 (file)
@@ -732,16 +732,17 @@ typedef u32 acpi_event_type;
  * The encoding of acpi_event_status is illustrated below.
  * Note that a set bit (1) indicates the property is TRUE
  * (e.g. if bit 0 is set then the event is enabled).
- * +-------------+-+-+-+-+-+
- * |   Bits 31:5 |4|3|2|1|0|
- * +-------------+-+-+-+-+-+
- *          |     | | | | |
- *          |     | | | | +- Enabled?
- *          |     | | | +--- Enabled for wake?
- *          |     | | +----- Status bit set?
- *          |     | +------- Enable bit set?
- *          |     +--------- Has a handler?
- *          +--------------- <Reserved>
+ * +-------------+-+-+-+-+-+-+
+ * |   Bits 31:6 |5|4|3|2|1|0|
+ * +-------------+-+-+-+-+-+-+
+ *          |     | | | | | |
+ *          |     | | | | | +- Enabled?
+ *          |     | | | | +--- Enabled for wake?
+ *          |     | | | +----- Status bit set?
+ *          |     | | +------- Enable bit set?
+ *          |     | +--------- Has a handler?
+ *          |     +----------- Masked?
+ *          +----------------- <Reserved>
  */
 typedef u32 acpi_event_status;
 
@@ -751,6 +752,7 @@ typedef u32 acpi_event_status;
 #define ACPI_EVENT_FLAG_STATUS_SET      (acpi_event_status) 0x04
 #define ACPI_EVENT_FLAG_ENABLE_SET      (acpi_event_status) 0x08
 #define ACPI_EVENT_FLAG_HAS_HANDLER     (acpi_event_status) 0x10
+#define ACPI_EVENT_FLAG_MASKED          (acpi_event_status) 0x20
 #define ACPI_EVENT_FLAG_SET             ACPI_EVENT_FLAG_STATUS_SET
 
 /* Actions for acpi_set_gpe, acpi_gpe_wakeup, acpi_hw_low_set_gpe */
@@ -761,14 +763,15 @@ typedef u32 acpi_event_status;
 
 /*
  * GPE info flags - Per GPE
- * +-------+-+-+---+
- * |  7:5  |4|3|2:0|
- * +-------+-+-+---+
- *     |    | |  |
- *     |    | |  +-- Type of dispatch:to method, handler, notify, or none
- *     |    | +----- Interrupt type: edge or level triggered
- *     |    +------- Is a Wake GPE
- *     +------------ <Reserved>
+ * +---+-+-+-+---+
+ * |7:6|5|4|3|2:0|
+ * +---+-+-+-+---+
+ *   |  | | |  |
+ *   |  | | |  +-- Type of dispatch:to method, handler, notify, or none
+ *   |  | | +----- Interrupt type: edge or level triggered
+ *   |  | +------- Is a Wake GPE
+ *   |  +--------- Is GPE masked by the software GPE masking machanism
+ *   +------------ <Reserved>
  */
 #define ACPI_GPE_DISPATCH_NONE          (u8) 0x00
 #define ACPI_GPE_DISPATCH_METHOD        (u8) 0x01