From aa6c74480f3bd638fae9457234264b36b912c853 Mon Sep 17 00:00:00 2001 From: Sarah Sharp Date: Fri, 16 Mar 2012 13:19:35 -0700 Subject: [PATCH] xhci: Fix register save/restore order. BugLink: http://bugs.launchpad.net/bugs/987337 commit c7713e736526d8c9f6f87716fb90562a8ffaff2c upstream. The xHCI 1.0 spec errata released on June 13, 2011, changes the ordering that the xHCI registers are saved and restored in. It moves the interrupt pending (IMAN) and interrupt control (IMOD) registers to be saved and restored last. I believe that's because the host controller may attempt to fetch the event ring table when interrupts are re-enabled. Therefore we need to restore the event ring registers before we re-enable interrupts. This should be backported to kernels as old as 2.6.37, that contain the commit 5535b1d5f8885695c6ded783c692e3c0d0eda8ca "USB: xHCI: PCI power management implementation" Signed-off-by: Sarah Sharp Tested-by: Elric Fu Cc: Andiry Xu Signed-off-by: Greg Kroah-Hartman Signed-off-by: Tim Gardner --- drivers/usb/host/xhci.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 0f92504..d90c5cd 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -664,11 +664,11 @@ static void xhci_save_registers(struct xhci_hcd *xhci) xhci->s3.dev_nt = xhci_readl(xhci, &xhci->op_regs->dev_notification); xhci->s3.dcbaa_ptr = xhci_read_64(xhci, &xhci->op_regs->dcbaa_ptr); xhci->s3.config_reg = xhci_readl(xhci, &xhci->op_regs->config_reg); - xhci->s3.irq_pending = xhci_readl(xhci, &xhci->ir_set->irq_pending); - xhci->s3.irq_control = xhci_readl(xhci, &xhci->ir_set->irq_control); xhci->s3.erst_size = xhci_readl(xhci, &xhci->ir_set->erst_size); xhci->s3.erst_base = xhci_read_64(xhci, &xhci->ir_set->erst_base); xhci->s3.erst_dequeue = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue); + xhci->s3.irq_pending = xhci_readl(xhci, &xhci->ir_set->irq_pending); + xhci->s3.irq_control = xhci_readl(xhci, &xhci->ir_set->irq_control); } static void xhci_restore_registers(struct xhci_hcd *xhci) @@ -677,11 +677,11 @@ static void xhci_restore_registers(struct xhci_hcd *xhci) xhci_writel(xhci, xhci->s3.dev_nt, &xhci->op_regs->dev_notification); xhci_write_64(xhci, xhci->s3.dcbaa_ptr, &xhci->op_regs->dcbaa_ptr); xhci_writel(xhci, xhci->s3.config_reg, &xhci->op_regs->config_reg); - xhci_writel(xhci, xhci->s3.irq_pending, &xhci->ir_set->irq_pending); - xhci_writel(xhci, xhci->s3.irq_control, &xhci->ir_set->irq_control); xhci_writel(xhci, xhci->s3.erst_size, &xhci->ir_set->erst_size); xhci_write_64(xhci, xhci->s3.erst_base, &xhci->ir_set->erst_base); xhci_write_64(xhci, xhci->s3.erst_dequeue, &xhci->ir_set->erst_dequeue); + xhci_writel(xhci, xhci->s3.irq_pending, &xhci->ir_set->irq_pending); + xhci_writel(xhci, xhci->s3.irq_control, &xhci->ir_set->irq_control); } static void xhci_set_cmd_ring_deq(struct xhci_hcd *xhci) -- 1.7.10.4