raspi/linux
1
0
Fork 1
mirror of https://github.com/raspberrypi/linux.git synced 2025-12-06 10:00:17 +00:00
Code Issues Projects Releases Wiki Activity

usb: xhci: add XHCI_VLI_HUB_TT_QUIRK

Browse Source 
The integrated USB2.0 hub in the VL805 chipset has a bug where it
incorrectly determines the remaining available frame time before the
host next sends a SOF packet with an incremented frame_number.

See the USB2.0 specification sections 11.3 and 11.14.2.3.

The hub's non-periodic TT handler can transmit the IN/OUT handshake
token too late, so a following 64-byte DATA0/1 packet causes the ACK
handshake to collide with the propagated SOF. This causes port babble.

Avoid ringing doorbells for vulnerable endpoints during uFrame 7 if the
TR is Idle to stop one source of babble. An IN transfer for a Running TR
may happen at any time, so there's not much we can do about that.

Ideally a hub firmware update to properly implement frame timeouts is
needed, and to avoid spinning for up to 125us when submitting TDs to
Idle rings.

Signed-off-by: Jonathan Bell <jonathan@raspberrypi.com>

xhci: constrain XHCI_VLI_HUB_TT_QUIRK to old firmware versions

VLI have a firmware update for the VL805 which resolves the incorrect
frame time calculation in the hub's TT. Limit applying the quirk to
known-bad firmwares.

Signed-off-by: Jonathan Bell <jonathan@raspberrypi.com>
This commit is contained in:
Jonathan Bell
2022-12-01 16:59:44 +00:00
committed by Dom Cobley
parent a05ff2c31a
commit 011e03134f
3 changed files with 61 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
drivers/usb/host/xhci-pci.c
View File

@@ -27,6 +27,8 @@
#define SPARSE_DISABLE_BIT 17
#define SPARSE_CNTL_ENABLE 0xC12C
#define VL805_FW_VER_0138C0 0x0138C0
/* Device for a quirk */
#define PCI_VENDOR_ID_FRESCO_LOGIC 0x1b73
#define PCI_DEVICE_ID_FRESCO_LOGIC_PDK 0x1000
@@ -248,6 +250,16 @@ static int xhci_pci_reinit(struct xhci_hcd *xhci, struct pci_dev *pdev)
return 0;
}
static u32 xhci_vl805_get_fw_version(struct pci_dev *dev)
{
int ret;
u32 ver;
ret = pci_read_config_dword(dev, 0x50, &ver);
/* Default to a fw version of 0 instead of ~0 */
return ret ? 0 : ver;
}
static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
{
struct pci_dev *pdev = to_pci_dev(dev);
@@ -451,6 +463,8 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
xhci->quirks |= XHCI_EP_CTX_BROKEN_DCS;
xhci->quirks |= XHCI_AVOID_DQ_ON_LINK;
xhci->quirks |= XHCI_VLI_SS_BULK_OUT_BUG;
if (xhci_vl805_get_fw_version(pdev) < VL805_FW_VER_0138C0)
xhci->quirks |= XHCI_VLI_HUB_TT_QUIRK;
}
if (pdev->vendor == PCI_VENDOR_ID_ASMEDIA &&

46
drivers/usb/host/xhci-ring.c
View File

@@ -3655,6 +3655,48 @@ static int xhci_align_td(struct xhci_hcd *xhci, struct urb *urb, u32 enqd_len,
return 1;
}
static void xhci_vl805_hub_tt_quirk(struct xhci_hcd *xhci, struct urb *urb,
struct xhci_ring *ring)
{
struct list_head *tmp;
struct usb_device *udev = urb->dev;
unsigned int timeout = 0;
unsigned int single_td = 0;
/*
* Adding a TD to an Idle ring for a FS nonperiodic endpoint
* that is behind the internal hub's TT will run the risk of causing a
* downstream port babble if submitted late in uFrame 7.
* Wait until we've moved on into at least uFrame 0
* (MFINDEX references the next SOF to be transmitted).
*
* Rings for IN endpoints in the Running state also risk causing
* babble if the returned data is large, but there's not much we can do
* about it here.
*/
if (udev->route & 0xffff0 || udev->speed != USB_SPEED_FULL)
return;
list_for_each(tmp, &ring->td_list) {
single_td++;
if (single_td == 2) {
single_td = 0;
break;
}
}
if (single_td) {
while (timeout < 20 &&
(readl(&xhci->run_regs->microframe_index) & 0x7) == 0) {
udelay(10);
timeout++;
}
if (timeout >= 20)
xhci_warn(xhci, "MFINDEX didn't advance - %u.%u dodged\n",
readl(&xhci->run_regs->microframe_index) >> 3,
readl(&xhci->run_regs->microframe_index) & 7);
}
}
/* This is very similar to what ehci-q.c qtd_fill() does */
int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
struct urb *urb, int slot_id, unsigned int ep_index)
@@ -3809,6 +3851,8 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
}
check_trb_math(urb, enqd_len);
if (xhci->quirks & XHCI_VLI_HUB_TT_QUIRK)
xhci_vl805_hub_tt_quirk(xhci, urb, ring);
giveback_first_trb(xhci, slot_id, ep_index, urb->stream_id,
start_cycle, start_trb);
return 0;
@@ -3957,6 +4001,8 @@ int xhci_queue_ctrl_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
/* Event on completion */
field | TRB_IOC | TRB_TYPE(TRB_STATUS) | ep_ring->cycle_state);
if (xhci->quirks & XHCI_VLI_HUB_TT_QUIRK)
xhci_vl805_hub_tt_quirk(xhci, urb, ep_ring);
giveback_first_trb(xhci, slot_id, ep_index, 0,
start_cycle, start_trb);
return 0;

1
drivers/usb/host/xhci.h
View File

@@ -1648,6 +1648,7 @@ struct xhci_hcd {
/* Downstream VLI fixes */
#define XHCI_AVOID_DQ_ON_LINK BIT_ULL(56)
#define XHCI_VLI_SS_BULK_OUT_BUG BIT_ULL(57)
#define XHCI_VLI_HUB_TT_QUIRK BIT_ULL(58)
unsigned int num_active_eps;
unsigned int limit_active_eps;