[RFC v4 3/3] vfio: platform: reset: add msi support

Vikas Gupta
2021-01-29T17:30:09Z

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Add msi support for Broadcom FlexRm device.

Signed-off-by: Vikas Gupta <vikas.gupta@broadcom.com>
---
.../platform/reset/vfio_platform_bcmflexrm.c | 72 ++++++++++++++++++-
1 file changed, 70 insertions(+), 2 deletions(-)

diff --git a/drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c b/drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c
index 96064ef8f629..6ca4ca12575b 100644
--- a/drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c
+++ b/drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c
@@ -21,7 +21,9 @@
#include <linux/init.h>
#include <linux/io.h>
#include <linux/kernel.h>
+#include <linux/msi.h>
#include <linux/module.h>
+#include <linux/vfio.h>

#include "../vfio_platform_private.h"

@@ -33,6 +35,9 @@
#define RING_VER 0x000
#define RING_CONTROL 0x034
#define RING_FLUSH_DONE 0x038
+#define RING_MSI_ADDR_LS 0x03c
+#define RING_MSI_ADDR_MS 0x040
+#define RING_MSI_DATA_VALUE 0x064

/* Register RING_CONTROL fields */
#define CONTROL_FLUSH_SHIFT 5
@@ -105,8 +110,71 @@ static int vfio_platform_bcmflexrm_reset(struct vfio_platform_device *vdev)
return ret;
}

-module_vfio_reset_handler("brcm,iproc-flexrm-mbox",
- vfio_platform_bcmflexrm_reset);
+static u32 bcm_num_msi(struct vfio_platform_device *vdev)
+{
+ struct vfio_platform_region *reg = &vdev->regions[0];
+
+ return (reg->size / RING_REGS_SIZE);
+}
+
+static void bcm_write_msi(struct vfio_platform_device *vdev,
+ struct msi_desc *desc,
+ struct msi_msg *msg)
+{
+ int i;
+ int hwirq = -1;
+ int msi_src;
+ void __iomem *ring;
+ struct vfio_platform_region *reg = &vdev->regions[0];
+
+ if (!reg)
+ return;
+
+ for (i = 0; i < vdev->num_irqs; i++)
+ if (vdev->irqs[i].type == VFIO_IRQ_TYPE_MSI)
+ hwirq = vdev->irqs[i].ctx[0].hwirq;
+
+ if (hwirq < 0)
+ return;
+
+ msi_src = desc->irq - hwirq;
+
+ if (!reg->ioaddr) {
+ reg->ioaddr = ioremap(reg->addr, reg->size);
+ if (!reg->ioaddr)
+ return;
+ }
+
+ ring = reg->ioaddr + msi_src * RING_REGS_SIZE;
+
+ writel_relaxed(msg->address_lo, ring + RING_MSI_ADDR_LS);
+ writel_relaxed(msg->address_hi, ring + RING_MSI_ADDR_MS);
+ writel_relaxed(msg->data, ring + RING_MSI_DATA_VALUE);
+}
+
+static struct vfio_platform_reset_node vfio_platform_bcmflexrm_reset_node = {
+ .owner = THIS_MODULE,
+ .compat = "brcm,iproc-flexrm-mbox",
+ .of_reset = vfio_platform_bcmflexrm_reset,
+ .of_get_msi = bcm_num_msi,
+ .of_msi_write = bcm_write_msi
+};
+
+static int __init vfio_platform_bcmflexrm_reset_module_init(void)
+{
+ __vfio_platform_register_reset(&vfio_platform_bcmflexrm_reset_node);
+
+ return 0;
+}
+
+static void __exit vfio_platform_bcmflexrm_reset_module_exit(void)
+{
+ vfio_platform_unregister_reset("brcm,iproc-flexrm-mbox",
+ vfio_platform_bcmflexrm_reset);
+}
+
+module_init(vfio_platform_bcmflexrm_reset_module_init);
+module_exit(vfio_platform_bcmflexrm_reset_module_exit);

MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Anup Patel <anup.patel@broadcom.com>");
--
2.17.1