xhci: add support to allocate several interrupters

Modify the XHCI drivers to accommodate for handling multiple event rings in
case there are multiple interrupters.  Add the required APIs so clients are
able to allocate/request for an interrupter ring, and pass this information
back to the client driver.  This allows for users to handle the resource
accordingly, such as passing the event ring base address to an audio DSP.
There is no actual support for multiple MSI/MSI-X vectors.

[export xhci_initialize_ring_info() -wcheng]

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Wesley Cheng <quic_wcheng@quicinc.com>
Link: https://lore.kernel.org/r/20240102214549.22498-2-quic_wcheng@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 33 insertions, 18 deletions

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 7d5b94905b9c..c057c42c36f4 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -480,7 +480,7 @@ static int xhci_init(struct usb_hcd *hcd)
 
 static int xhci_run_finished(struct xhci_hcd *xhci)
 {
-	struct xhci_interrupter *ir = xhci->interrupter;
+	struct xhci_interrupter *ir = xhci->interrupters[0];
 	unsigned long	flags;
 	u32		temp;
 
@@ -532,7 +532,7 @@ int xhci_run(struct usb_hcd *hcd)
 	u64 temp_64;
 	int ret;
 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
-	struct xhci_interrupter *ir = xhci->interrupter;
+	struct xhci_interrupter *ir = xhci->interrupters[0];
 	/* Start the xHCI host controller running only after the USB 2.0 roothub
 	 * is setup.
 	 */
@@ -596,7 +596,7 @@ void xhci_stop(struct usb_hcd *hcd)
 {
 	u32 temp;
 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
-	struct xhci_interrupter *ir = xhci->interrupter;
+	struct xhci_interrupter *ir = xhci->interrupters[0];
 
 	mutex_lock(&xhci->mutex);
 
@@ -692,36 +692,51 @@ EXPORT_SYMBOL_GPL(xhci_shutdown);
 #ifdef CONFIG_PM
 static void xhci_save_registers(struct xhci_hcd *xhci)
 {
-	struct xhci_interrupter *ir = xhci->interrupter;
+	struct xhci_interrupter *ir;
+	unsigned int i;
 
 	xhci->s3.command = readl(&xhci->op_regs->command);
 	xhci->s3.dev_nt = readl(&xhci->op_regs->dev_notification);
 	xhci->s3.dcbaa_ptr = xhci_read_64(xhci, &xhci->op_regs->dcbaa_ptr);
 	xhci->s3.config_reg = readl(&xhci->op_regs->config_reg);
 
-	if (!ir)
-		return;
+	/* save both primary and all secondary interrupters */
+	/* fixme, shold we lock  to prevent race with remove secondary interrupter? */
+	for (i = 0; i < xhci->max_interrupters; i++) {
+		ir = xhci->interrupters[i];
+		if (!ir)
+			continue;
 
-	ir->s3_erst_size = readl(&ir->ir_set->erst_size);
-	ir->s3_erst_base = xhci_read_64(xhci, &ir->ir_set->erst_base);
-	ir->s3_erst_dequeue = xhci_read_64(xhci, &ir->ir_set->erst_dequeue);
-	ir->s3_irq_pending = readl(&ir->ir_set->irq_pending);
-	ir->s3_irq_control = readl(&ir->ir_set->irq_control);
+		ir->s3_erst_size = readl(&ir->ir_set->erst_size);
+		ir->s3_erst_base = xhci_read_64(xhci, &ir->ir_set->erst_base);
+		ir->s3_erst_dequeue = xhci_read_64(xhci, &ir->ir_set->erst_dequeue);
+		ir->s3_irq_pending = readl(&ir->ir_set->irq_pending);
+		ir->s3_irq_control = readl(&ir->ir_set->irq_control);
+	}
 }
 
 static void xhci_restore_registers(struct xhci_hcd *xhci)
 {
-	struct xhci_interrupter *ir = xhci->interrupter;
+	struct xhci_interrupter *ir;
+	unsigned int i;
 
 	writel(xhci->s3.command, &xhci->op_regs->command);
 	writel(xhci->s3.dev_nt, &xhci->op_regs->dev_notification);
 	xhci_write_64(xhci, xhci->s3.dcbaa_ptr, &xhci->op_regs->dcbaa_ptr);
 	writel(xhci->s3.config_reg, &xhci->op_regs->config_reg);
-	writel(ir->s3_erst_size, &ir->ir_set->erst_size);
-	xhci_write_64(xhci, ir->s3_erst_base, &ir->ir_set->erst_base);
-	xhci_write_64(xhci, ir->s3_erst_dequeue, &ir->ir_set->erst_dequeue);
-	writel(ir->s3_irq_pending, &ir->ir_set->irq_pending);
-	writel(ir->s3_irq_control, &ir->ir_set->irq_control);
+
+	/* FIXME should we lock to protect against freeing of interrupters */
+	for (i = 0; i < xhci->max_interrupters; i++) {
+		ir = xhci->interrupters[i];
+		if (!ir)
+			continue;
+
+		writel(ir->s3_erst_size, &ir->ir_set->erst_size);
+		xhci_write_64(xhci, ir->s3_erst_base, &ir->ir_set->erst_base);
+		xhci_write_64(xhci, ir->s3_erst_dequeue, &ir->ir_set->erst_dequeue);
+		writel(ir->s3_irq_pending, &ir->ir_set->irq_pending);
+		writel(ir->s3_irq_control, &ir->ir_set->irq_control);
+	}
 }
 
 static void xhci_set_cmd_ring_deq(struct xhci_hcd *xhci)
@@ -1084,7 +1099,7 @@ int xhci_resume(struct xhci_hcd *xhci, pm_message_t msg)
 		xhci_dbg(xhci, "// Disabling event ring interrupts\n");
 		temp = readl(&xhci->op_regs->status);
 		writel((temp & ~0x1fff) | STS_EINT, &xhci->op_regs->status);
-		xhci_disable_interrupter(xhci->interrupter);
+		xhci_disable_interrupter(xhci->interrupters[0]);
 
 		xhci_dbg(xhci, "cleaning up memory\n");
 		xhci_mem_cleanup(xhci);