[coreboot] New patch to review for coreboot: 2f51d92 libpayload: Add timeouts in the EHCI USB driver
Nico Huber (nico.huber@secunet.com)
gerrit at coreboot.org
Thu May 31 15:41:34 CEST 2012
Nico Huber (nico.huber at secunet.com) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/1077
-gerrit
commit 2f51d9239824baaac28029b5cabb69f1cad06236
Author: Nico Huber <nico.huber at secunet.com>
Date: Mon May 21 14:53:43 2012 +0200
libpayload: Add timeouts in the EHCI USB driver
We should always have some timeout when we wait for the hardware. This adds
missing timeouts to the EHCI driver.
Change-Id: I13ba532a6daf47510b16b8fdbe572a21f1d8b09c
Signed-off-by: Nico Huber <nico.huber at secunet.com>
---
payloads/libpayload/drivers/usb/ehci.c | 90 ++++++++++++++++++++--------
payloads/libpayload/drivers/usb/ehci_rh.c | 32 +++++++++--
2 files changed, 91 insertions(+), 31 deletions(-)
diff --git a/payloads/libpayload/drivers/usb/ehci.c b/payloads/libpayload/drivers/usb/ehci.c
index 9500059..cd1e867 100644
--- a/payloads/libpayload/drivers/usb/ehci.c
+++ b/payloads/libpayload/drivers/usb/ehci.c
@@ -116,7 +116,21 @@ static int wait_for_tds(qtd_t *head)
qtd_t *cur = head;
while (1) {
if (0) dump_td(virt_to_phys(cur));
- while ((cur->token & QTD_ACTIVE) && !(cur->token & QTD_HALTED)) udelay(60);
+
+ /* wait for results */
+ /* TOTEST: how long to wait?
+ * tested with some USB2.0 flash sticks:
+ * slowest took around 180ms
+ */
+ int timeout = 10000; /* time out after 10000 * 50us == 500ms */
+ while ((cur->token & QTD_ACTIVE) && !(cur->token & QTD_HALTED)
+ && timeout--)
+ udelay(50);
+ if (timeout < 0) {
+ printf("Error: ehci: queue transfer "
+ "processing timed out.\n");
+ return 1;
+ }
if (cur->token & QTD_HALTED) {
printf("ERROR with packet\n");
dump_td(virt_to_phys(cur));
@@ -134,6 +148,51 @@ static int wait_for_tds(qtd_t *head)
return result;
}
+static int ehci_set_async_schedule(ehci_t *ehcic, int enable)
+{
+ /* Set async schedule status. */
+ if (enable)
+ ehcic->operation->usbcmd |= HC_OP_ASYNC_SCHED_EN;
+ else
+ ehcic->operation->usbcmd &= ~HC_OP_ASYNC_SCHED_EN;
+ /* Wait for the controller to accept async schedule status.
+ * This shouldn't take too long, but we should timeout nevertheless.
+ */
+ enable = enable ? HC_OP_ASYNC_SCHED_STAT : 0;
+ int timeout = 100; /* time out after 100ms */
+ while (((ehcic->operation->usbsts & HC_OP_ASYNC_SCHED_STAT) != enable)
+ && timeout--)
+ mdelay(1);
+ if (timeout < 0) {
+ debug("ehci async schedule status change timed out.\n");
+ return 1;
+ }
+ return 0;
+}
+
+static int ehci_process_async_schedule(
+ ehci_t *ehcic, ehci_qh_t *qhead, qtd_t *head)
+{
+ int result;
+
+ /* make sure async schedule is disabled */
+ if (ehci_set_async_schedule(ehcic, 0)) return 1;
+
+ /* hook up QH */
+ ehcic->operation->asynclistaddr = virt_to_phys(qhead);
+
+ /* start async schedule */
+ if (ehci_set_async_schedule(ehcic, 1)) return 1;
+
+ /* wait for result */
+ result = wait_for_tds(head);
+
+ /* disable async schedule */
+ ehci_set_async_schedule(ehcic, 0);
+
+ return result;
+}
+
static int ehci_bulk (endpoint_t *ep, int size, u8 *data, int finalize)
{
int result = 0;
@@ -179,19 +238,8 @@ static int ehci_bulk (endpoint_t *ep, int size, u8 *data, int finalize)
qh->td.token |= (ep->toggle?QTD_TOGGLE_DATA1:0);
head->token |= (ep->toggle?QTD_TOGGLE_DATA1:0);
- /* hook up QH */
- EHCI_INST(ep->dev->controller)->operation->asynclistaddr = virt_to_phys(qh);
-
- /* start async schedule */
- EHCI_INST(ep->dev->controller)->operation->usbcmd |= HC_OP_ASYNC_SCHED_EN;
- while (!(EHCI_INST(ep->dev->controller)->operation->usbsts & HC_OP_ASYNC_SCHED_STAT)) ; /* wait */
-
- /* wait for result */
- result = wait_for_tds(head);
-
- /* disable async schedule */
- EHCI_INST(ep->dev->controller)->operation->usbcmd &= ~HC_OP_ASYNC_SCHED_EN;
- while (EHCI_INST(ep->dev->controller)->operation->usbsts & HC_OP_ASYNC_SCHED_STAT) ; /* wait */
+ result = ehci_process_async_schedule(
+ EHCI_INST(ep->dev->controller), qh, head);
ep->toggle = (cur->token & QTD_TOGGLE_MASK) >> QTD_TOGGLE_SHIFT;
@@ -268,18 +316,8 @@ static int ehci_control (usbdev_t *dev, direction_t dir, int drlen, void *devreq
qh->epcaps = 3 << QH_PIPE_MULTIPLIER_SHIFT;
qh->td.next_qtd = virt_to_phys(head);
- /* hook up QH */
- EHCI_INST(dev->controller)->operation->asynclistaddr = virt_to_phys(qh);
-
- /* start async schedule */
- EHCI_INST(dev->controller)->operation->usbcmd |= HC_OP_ASYNC_SCHED_EN;
- while (!(EHCI_INST(dev->controller)->operation->usbsts & HC_OP_ASYNC_SCHED_STAT)) ; /* wait */
-
- result = wait_for_tds(head);
-
- /* disable async schedule */
- EHCI_INST(dev->controller)->operation->usbcmd &= ~HC_OP_ASYNC_SCHED_EN;
- while (EHCI_INST(dev->controller)->operation->usbsts & HC_OP_ASYNC_SCHED_STAT) ; /* wait */
+ result = ehci_process_async_schedule(
+ EHCI_INST(dev->controller), qh, head);
free_qh_and_tds(qh, head);
return result;
diff --git a/payloads/libpayload/drivers/usb/ehci_rh.c b/payloads/libpayload/drivers/usb/ehci_rh.c
index dd073a3..aeead3b 100644
--- a/payloads/libpayload/drivers/usb/ehci_rh.c
+++ b/payloads/libpayload/drivers/usb/ehci_rh.c
@@ -55,9 +55,21 @@ ehci_rh_hand_over_port (usbdev_t *dev, int port)
{
debug("giving up port %x, it's USB1\n", port+1);
+ /* Clear ConnectStatusChange before evaluation */
+ /* RW/C register, so clear it by writing 1 */
+ RH_INST(dev)->ports[port] |= P_CONN_STATUS_CHANGE;
+
/* Lowspeed device. Hand over to companion */
RH_INST(dev)->ports[port] |= P_PORT_OWNER;
- do {} while (!(RH_INST(dev)->ports[port] & P_CONN_STATUS_CHANGE));
+
+ /* TOTEST: how long to wait? trying 100ms for now */
+ int timeout = 10; /* timeout after 10 * 10ms == 100ms */
+ while (!(RH_INST(dev)->ports[port] & P_CONN_STATUS_CHANGE) && timeout--)
+ mdelay(10);
+ if (!(RH_INST(dev)->ports[port] & P_CONN_STATUS_CHANGE)) {
+ debug("Warning: Handing port over to companion timed out.\n");
+ }
+
/* RW/C register, so clear it by writing 1 */
RH_INST(dev)->ports[port] |= P_CONN_STATUS_CHANGE;
return;
@@ -73,7 +85,7 @@ ehci_rh_scanport (usbdev_t *dev, int port)
}
/* device connected, handle */
if (RH_INST(dev)->ports[port] & P_CURR_CONN_STATUS) {
- mdelay(100);
+ mdelay(100); // usb20 spec 9.1.2
if ((RH_INST(dev)->ports[port] & P_LINE_STATUS) == P_LINE_STATUS_LOWSPEED) {
ehci_rh_hand_over_port(dev, port);
return;
@@ -85,13 +97,23 @@ ehci_rh_scanport (usbdev_t *dev, int port)
RH_INST(dev)->ports[port] = (RH_INST(dev)->ports[port] & ~P_PORT_ENABLE) | P_PORT_RESET;
/* Wait a bit while reset is active. */
- mdelay(50);
+ mdelay(50); // usb20 spec 7.1.7.5 (TDRSTR)
/* Deassert reset. */
RH_INST(dev)->ports[port] &= ~P_PORT_RESET;
- /* Wait for flag change to finish. The controller might take a while */
- while (RH_INST(dev)->ports[port] & P_PORT_RESET) ;
+ /* Wait max. 2ms (ehci spec 2.3.9) for flag change to finish. */
+ int timeout = 20; /* time out after 20 * 100us == 2ms */
+ while ((RH_INST(dev)->ports[port] & P_PORT_RESET) && timeout--)
+ udelay(100);
+ if (RH_INST(dev)->ports[port] & P_PORT_RESET) {
+ printf("Error: ehci_rh: port reset timed out.\n");
+ return;
+ }
+
+ /* If the host controller enabled the port, it's a high-speed
+ * device, otherwise it's full-speed.
+ */
if (!(RH_INST(dev)->ports[port] & P_PORT_ENABLE)) {
ehci_rh_hand_over_port(dev, port);
return;
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