[PATCH RFC 05/15] ims-msi: Add mask/unmask routines

From: Dave Jiang
Date: Tue Apr 21 2020 - 19:34:22 EST


From: Megha Dey <megha.dey@xxxxxxxxxxxxxxx>

Introduce the mask/unmask functions which would be used as callbacks
to the IRQ chip associated with the IMS domain.

Signed-off-by: Megha Dey <megha.dey@xxxxxxxxxxxxxxx>
---
drivers/base/ims-msi.c | 47 +++++++++++++++++++++++++++++++++++++++++++
drivers/base/platform-msi.c | 12 -----------
include/linux/msi.h | 14 +++++++++++++
3 files changed, 61 insertions(+), 12 deletions(-)

diff --git a/drivers/base/ims-msi.c b/drivers/base/ims-msi.c
index 738f6d153155..896a5a1b2252 100644
--- a/drivers/base/ims-msi.c
+++ b/drivers/base/ims-msi.c
@@ -7,11 +7,56 @@
* Author: Megha Dey <megha.dey@xxxxxxxxx>
*/

+#include <linux/device.h>
#include <linux/dmar.h>
+#include <linux/export.h>
#include <linux/irq.h>
#include <linux/mdev.h>
+#include <linux/msi.h>
#include <linux/pci.h>

+static u32 __dev_ims_desc_mask_irq(struct msi_desc *desc, u32 flag)
+{
+ u32 mask_bits = desc->platform.masked;
+ const struct platform_msi_ops *ops;
+
+ ops = desc->platform.msi_priv_data->ops;
+ if (!ops)
+ return 0;
+
+ if (flag) {
+ if (ops->irq_mask)
+ mask_bits = ops->irq_mask(desc);
+ } else {
+ if (ops->irq_unmask)
+ mask_bits = ops->irq_unmask(desc);
+ }
+
+ return mask_bits;
+}
+
+/**
+ * dev_ims_mask_irq - Generic irq chip callback to mask IMS interrupts
+ * @data: pointer to irqdata associated to that interrupt
+ */
+static void dev_ims_mask_irq(struct irq_data *data)
+{
+ struct msi_desc *desc = irq_data_get_msi_desc(data);
+
+ desc->platform.masked = __dev_ims_desc_mask_irq(desc, 1);
+}
+
+/**
+ * dev_msi_unmask_irq - Generic irq chip callback to unmask IMS interrupts
+ * @data: pointer to irqdata associated to that interrupt
+ */
+void dev_ims_unmask_irq(struct irq_data *data)
+{
+ struct msi_desc *desc = irq_data_get_msi_desc(data);
+
+ desc->platform.masked = __dev_ims_desc_mask_irq(desc, 0);
+}
+
/*
* Determine if a dev is mdev or not. Return NULL if not mdev device.
* Return mdev's parent dev if success.
@@ -69,6 +114,8 @@ static struct irq_chip dev_ims_ir_controller = {
.irq_set_vcpu_affinity = irq_chip_set_vcpu_affinity_parent,
.flags = IRQCHIP_SKIP_SET_WAKE,
.irq_write_msi_msg = platform_msi_write_msg,
+ .irq_unmask = dev_ims_unmask_irq,
+ .irq_mask = dev_ims_mask_irq,
};

static struct msi_domain_info ims_ir_domain_info = {
diff --git a/drivers/base/platform-msi.c b/drivers/base/platform-msi.c
index 59160e8cbfb1..6d8840db4a85 100644
--- a/drivers/base/platform-msi.c
+++ b/drivers/base/platform-msi.c
@@ -16,18 +16,6 @@
#define DEV_ID_SHIFT 21
#define MAX_DEV_MSIS (1 << (32 - DEV_ID_SHIFT))

-/*
- * Internal data structure containing a (made up, but unique) devid
- * and the callback to write the MSI message.
- */
-struct platform_msi_priv_data {
- struct device *dev;
- void *host_data;
- msi_alloc_info_t arg;
- const struct platform_msi_ops *ops;
- int devid;
-};
-
/* The devid allocator */
static DEFINE_IDA(platform_msi_devid_ida);

diff --git a/include/linux/msi.h b/include/linux/msi.h
index 80386468a7bc..8b5f24bf3c47 100644
--- a/include/linux/msi.h
+++ b/include/linux/msi.h
@@ -33,10 +33,12 @@ typedef void (*irq_write_msi_msg_t)(struct msi_desc *desc,
* platform_msi_desc - Platform device specific msi descriptor data
* @msi_priv_data: Pointer to platform private data
* @msi_index: The index of the MSI descriptor for multi MSI
+ * @masked: mask bits
*/
struct platform_msi_desc {
struct platform_msi_priv_data *msi_priv_data;
u16 msi_index;
+ u32 masked;
};

/**
@@ -370,6 +372,18 @@ struct platform_msi_ops {
irq_write_msi_msg_t write_msg;
};

+/*
+ * Internal data structure containing a (made up, but unique) devid
+ * and the callback to write the MSI message.
+ */
+struct platform_msi_priv_data {
+ struct device *dev;
+ void *host_data;
+ msi_alloc_info_t arg;
+ const struct platform_msi_ops *ops;
+ int devid;
+};
+
int msi_domain_set_affinity(struct irq_data *data, const struct cpumask *mask,
bool force);