| Message ID | 1448039188-14296-2-git-send-email-dianders@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 11/20/2015 9:06 AM, Douglas Anderson wrote: > In general it is wise to clear interrupts before processing them. If > you don't do that, you can get: > 1. Interrupt happens > 2. You look at system state and process interrupt > 3. A new interrupt happens > 4. You clear interrupt without processing it. > > This patch was actually a first attempt to fix missing device insertions > as described in (usb: dwc2: host: Fix missing device insertions) and it > did solve some of the signal bouncing problems but not all of > them (which is why I submitted the other patch). Specifically, this > patch itself would sometimes change: > 1. hardware sees connect > 2. hardware sees disconnect > 3. hardware sees connect > 4. dwc2_port_intr() - clears connect interrupt > 5. dwc2_handle_common_intr() - calls dwc2_hcd_disconnect() > > ...to: > 1. hardware sees connect > 2. hardware sees disconnect > 3. dwc2_port_intr() - clears connect interrupt > 4. hardware sees connect > 5. dwc2_handle_common_intr() - calls dwc2_hcd_disconnect() > > ...but with different timing then sometimes we'd still miss cable > insertions. > > In any case, though this patch doesn't fix any (known) problems, it > still seems wise as a general policy to clear interrupt before handling > them. > > Note that for dwc2_handle_usb_port_intr(), instead of moving the clear > of PRTINT to the beginning of the function we remove it completely. The > only way to clear PRTINT is to clear the sources that set it in the > first place. > > Signed-off-by: Douglas Anderson <dianders@chromium.org> > --- > Changes in v5: > - Rebased upon testing/next from 15-11-20. > - Fixed missing reset as found by code inspection during rebase. > - Now atop fix for missing spinlock in reset. > - Dropped John Youn's ack / tested by since there's a bugfix now. > > Changes in v4: > - Don't replace dwc2_writel with writel (Antti Seppälä). > - Update description to explain why we remove PRTINT clear. > > Changes in v3: > - Don't (uselessly) clear the PRTINT anymore (Felipe Balbi). > > drivers/usb/dwc2/core_intr.c | 49 +++++++++++++++++++++----------------------- > drivers/usb/dwc2/hcd_intr.c | 18 ++++++++-------- > 2 files changed, 32 insertions(+), 35 deletions(-) > > diff --git a/drivers/usb/dwc2/core_intr.c b/drivers/usb/dwc2/core_intr.c > index 61601d16e233..d85c5c9f96c1 100644 > --- a/drivers/usb/dwc2/core_intr.c > +++ b/drivers/usb/dwc2/core_intr.c > @@ -86,9 +86,6 @@ static void dwc2_handle_usb_port_intr(struct dwc2_hsotg *hsotg) > hprt0 &= ~HPRT0_ENA; > dwc2_writel(hprt0, hsotg->regs + HPRT0); > } > - > - /* Clear interrupt */ > - dwc2_writel(GINTSTS_PRTINT, hsotg->regs + GINTSTS); > } > > /** > @@ -98,11 +95,11 @@ static void dwc2_handle_usb_port_intr(struct dwc2_hsotg *hsotg) > */ > static void dwc2_handle_mode_mismatch_intr(struct dwc2_hsotg *hsotg) > { > - dev_warn(hsotg->dev, "Mode Mismatch Interrupt: currently in %s mode\n", > - dwc2_is_host_mode(hsotg) ? "Host" : "Device"); > - > /* Clear interrupt */ > dwc2_writel(GINTSTS_MODEMIS, hsotg->regs + GINTSTS); > + > + dev_warn(hsotg->dev, "Mode Mismatch Interrupt: currently in %s mode\n", > + dwc2_is_host_mode(hsotg) ? "Host" : "Device"); > } > > /** > @@ -276,9 +273,13 @@ static void dwc2_handle_otg_intr(struct dwc2_hsotg *hsotg) > */ > static void dwc2_handle_conn_id_status_change_intr(struct dwc2_hsotg *hsotg) > { > - u32 gintmsk = dwc2_readl(hsotg->regs + GINTMSK); > + u32 gintmsk; > + > + /* Clear interrupt */ > + dwc2_writel(GINTSTS_CONIDSTSCHNG, hsotg->regs + GINTSTS); > > /* Need to disable SOF interrupt immediately */ > + gintmsk = dwc2_readl(hsotg->regs + GINTMSK); > gintmsk &= ~GINTSTS_SOF; > dwc2_writel(gintmsk, hsotg->regs + GINTMSK); > > @@ -295,9 +296,6 @@ static void dwc2_handle_conn_id_status_change_intr(struct dwc2_hsotg *hsotg) > queue_work(hsotg->wq_otg, &hsotg->wf_otg); > spin_lock(&hsotg->lock); > } > - > - /* Clear interrupt */ > - dwc2_writel(GINTSTS_CONIDSTSCHNG, hsotg->regs + GINTSTS); > } > > /** > @@ -315,12 +313,12 @@ static void dwc2_handle_session_req_intr(struct dwc2_hsotg *hsotg) > { > int ret; > > - dev_dbg(hsotg->dev, "Session request interrupt - lx_state=%d\n", > - hsotg->lx_state); > - > /* Clear interrupt */ > dwc2_writel(GINTSTS_SESSREQINT, hsotg->regs + GINTSTS); > > + dev_dbg(hsotg->dev, "Session request interrupt - lx_state=%d\n", > + hsotg->lx_state); > + > if (dwc2_is_device_mode(hsotg)) { > if (hsotg->lx_state == DWC2_L2) { > ret = dwc2_exit_hibernation(hsotg, true); > @@ -347,6 +345,10 @@ static void dwc2_handle_session_req_intr(struct dwc2_hsotg *hsotg) > static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg) > { > int ret; > + > + /* Clear interrupt */ > + dwc2_writel(GINTSTS_WKUPINT, hsotg->regs + GINTSTS); > + > dev_dbg(hsotg->dev, "++Resume or Remote Wakeup Detected Interrupt++\n"); > dev_dbg(hsotg->dev, "%s lxstate = %d\n", __func__, hsotg->lx_state); > > @@ -368,10 +370,9 @@ static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg) > /* Change to L0 state */ > hsotg->lx_state = DWC2_L0; > } else { > - if (hsotg->core_params->hibernation) { > - dwc2_writel(GINTSTS_WKUPINT, hsotg->regs + GINTSTS); > + if (hsotg->core_params->hibernation) > return; > - } > + > if (hsotg->lx_state != DWC2_L1) { > u32 pcgcctl = dwc2_readl(hsotg->regs + PCGCTL); > > @@ -385,9 +386,6 @@ static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg) > hsotg->lx_state = DWC2_L0; > } > } > - > - /* Clear interrupt */ > - dwc2_writel(GINTSTS_WKUPINT, hsotg->regs + GINTSTS); > } > > /* > @@ -396,14 +394,14 @@ static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg) > */ > static void dwc2_handle_disconnect_intr(struct dwc2_hsotg *hsotg) > { > + dwc2_writel(GINTSTS_DISCONNINT, hsotg->regs + GINTSTS); > + > dev_dbg(hsotg->dev, "++Disconnect Detected Interrupt++ (%s) %s\n", > dwc2_is_host_mode(hsotg) ? "Host" : "Device", > dwc2_op_state_str(hsotg)); > > if (hsotg->op_state == OTG_STATE_A_HOST) > dwc2_hcd_disconnect(hsotg, false); > - > - dwc2_writel(GINTSTS_DISCONNINT, hsotg->regs + GINTSTS); > } > > /* > @@ -419,6 +417,9 @@ static void dwc2_handle_usb_suspend_intr(struct dwc2_hsotg *hsotg) > u32 dsts; > int ret; > > + /* Clear interrupt */ > + dwc2_writel(GINTSTS_USBSUSP, hsotg->regs + GINTSTS); > + > dev_dbg(hsotg->dev, "USB SUSPEND\n"); > > if (dwc2_is_device_mode(hsotg)) { > @@ -437,7 +438,7 @@ static void dwc2_handle_usb_suspend_intr(struct dwc2_hsotg *hsotg) > if (!dwc2_is_device_connected(hsotg)) { > dev_dbg(hsotg->dev, > "ignore suspend request before enumeration\n"); > - goto clear_int; > + return; > } > > ret = dwc2_enter_hibernation(hsotg); > @@ -476,10 +477,6 @@ skip_power_saving: > hsotg->op_state = OTG_STATE_A_HOST; > } > } > - > -clear_int: > - /* Clear interrupt */ > - dwc2_writel(GINTSTS_USBSUSP, hsotg->regs + GINTSTS); > } > > #define GINTMSK_COMMON (GINTSTS_WKUPINT | GINTSTS_SESSREQINT | \ > diff --git a/drivers/usb/dwc2/hcd_intr.c b/drivers/usb/dwc2/hcd_intr.c > index a1eb48e54858..f8253803a050 100644 > --- a/drivers/usb/dwc2/hcd_intr.c > +++ b/drivers/usb/dwc2/hcd_intr.c > @@ -122,6 +122,9 @@ static void dwc2_sof_intr(struct dwc2_hsotg *hsotg) > struct dwc2_qh *qh; > enum dwc2_transaction_type tr_type; > > + /* Clear interrupt */ > + dwc2_writel(GINTSTS_SOF, hsotg->regs + GINTSTS); > + > #ifdef DEBUG_SOF > dev_vdbg(hsotg->dev, "--Start of Frame Interrupt--\n"); > #endif > @@ -146,9 +149,6 @@ static void dwc2_sof_intr(struct dwc2_hsotg *hsotg) > tr_type = dwc2_hcd_select_transactions(hsotg); > if (tr_type != DWC2_TRANSACTION_NONE) > dwc2_hcd_queue_transactions(hsotg, tr_type); > - > - /* Clear interrupt */ > - dwc2_writel(GINTSTS_SOF, hsotg->regs + GINTSTS); > } > > /* > @@ -312,6 +312,7 @@ static void dwc2_hprt0_enable(struct dwc2_hsotg *hsotg, u32 hprt0, > > if (do_reset) { > *hprt0_modify |= HPRT0_RST; > + dwc2_writel(*hprt0_modify, hsotg->regs + HPRT0); > queue_delayed_work(hsotg->wq_otg, &hsotg->reset_work, > msecs_to_jiffies(60)); > } else { > @@ -347,11 +348,12 @@ static void dwc2_port_intr(struct dwc2_hsotg *hsotg) > * Set flag and clear if detected > */ > if (hprt0 & HPRT0_CONNDET) { > + dwc2_writel(hprt0_modify | HPRT0_CONNDET, hsotg->regs + HPRT0); > + > dev_vdbg(hsotg->dev, > "--Port Interrupt HPRT0=0x%08x Port Connect Detected--\n", > hprt0); > dwc2_hcd_connect(hsotg); > - hprt0_modify |= HPRT0_CONNDET; > > /* > * The Hub driver asserts a reset when it sees port connect > @@ -364,10 +366,10 @@ static void dwc2_port_intr(struct dwc2_hsotg *hsotg) > * Clear if detected - Set internal flag if disabled > */ > if (hprt0 & HPRT0_ENACHG) { > + dwc2_writel(hprt0_modify | HPRT0_ENACHG, hsotg->regs + HPRT0); > dev_vdbg(hsotg->dev, > " --Port Interrupt HPRT0=0x%08x Port Enable Changed (now %d)--\n", > hprt0, !!(hprt0 & HPRT0_ENA)); > - hprt0_modify |= HPRT0_ENACHG; > if (hprt0 & HPRT0_ENA) { > hsotg->new_connection = true; > dwc2_hprt0_enable(hsotg, hprt0, &hprt0_modify); > @@ -387,15 +389,13 @@ static void dwc2_port_intr(struct dwc2_hsotg *hsotg) > > /* Overcurrent Change Interrupt */ > if (hprt0 & HPRT0_OVRCURRCHG) { > + dwc2_writel(hprt0_modify | HPRT0_OVRCURRCHG, > + hsotg->regs + HPRT0); > dev_vdbg(hsotg->dev, > " --Port Interrupt HPRT0=0x%08x Port Overcurrent Changed--\n", > hprt0); > hsotg->flags.b.port_over_current_change = 1; > - hprt0_modify |= HPRT0_OVRCURRCHG; > } > - > - /* Clear Port Interrupts */ > - dwc2_writel(hprt0_modify, hsotg->regs + HPRT0); > } > > /* > Acked-by: John Youn <johnyoun@synopsys.com> Tested-by: John Youn <johnyoun@synopsys.com> Tested on IP v3.20 on HAPS PCI system. Regards, John
diff --git a/drivers/usb/dwc2/core_intr.c b/drivers/usb/dwc2/core_intr.c index 61601d16e233..d85c5c9f96c1 100644 --- a/drivers/usb/dwc2/core_intr.c +++ b/drivers/usb/dwc2/core_intr.c @@ -86,9 +86,6 @@ static void dwc2_handle_usb_port_intr(struct dwc2_hsotg *hsotg) hprt0 &= ~HPRT0_ENA; dwc2_writel(hprt0, hsotg->regs + HPRT0); } - - /* Clear interrupt */ - dwc2_writel(GINTSTS_PRTINT, hsotg->regs + GINTSTS); } /** @@ -98,11 +95,11 @@ static void dwc2_handle_usb_port_intr(struct dwc2_hsotg *hsotg) */ static void dwc2_handle_mode_mismatch_intr(struct dwc2_hsotg *hsotg) { - dev_warn(hsotg->dev, "Mode Mismatch Interrupt: currently in %s mode\n", - dwc2_is_host_mode(hsotg) ? "Host" : "Device"); - /* Clear interrupt */ dwc2_writel(GINTSTS_MODEMIS, hsotg->regs + GINTSTS); + + dev_warn(hsotg->dev, "Mode Mismatch Interrupt: currently in %s mode\n", + dwc2_is_host_mode(hsotg) ? "Host" : "Device"); } /** @@ -276,9 +273,13 @@ static void dwc2_handle_otg_intr(struct dwc2_hsotg *hsotg) */ static void dwc2_handle_conn_id_status_change_intr(struct dwc2_hsotg *hsotg) { - u32 gintmsk = dwc2_readl(hsotg->regs + GINTMSK); + u32 gintmsk; + + /* Clear interrupt */ + dwc2_writel(GINTSTS_CONIDSTSCHNG, hsotg->regs + GINTSTS); /* Need to disable SOF interrupt immediately */ + gintmsk = dwc2_readl(hsotg->regs + GINTMSK); gintmsk &= ~GINTSTS_SOF; dwc2_writel(gintmsk, hsotg->regs + GINTMSK); @@ -295,9 +296,6 @@ static void dwc2_handle_conn_id_status_change_intr(struct dwc2_hsotg *hsotg) queue_work(hsotg->wq_otg, &hsotg->wf_otg); spin_lock(&hsotg->lock); } - - /* Clear interrupt */ - dwc2_writel(GINTSTS_CONIDSTSCHNG, hsotg->regs + GINTSTS); } /** @@ -315,12 +313,12 @@ static void dwc2_handle_session_req_intr(struct dwc2_hsotg *hsotg) { int ret; - dev_dbg(hsotg->dev, "Session request interrupt - lx_state=%d\n", - hsotg->lx_state); - /* Clear interrupt */ dwc2_writel(GINTSTS_SESSREQINT, hsotg->regs + GINTSTS); + dev_dbg(hsotg->dev, "Session request interrupt - lx_state=%d\n", + hsotg->lx_state); + if (dwc2_is_device_mode(hsotg)) { if (hsotg->lx_state == DWC2_L2) { ret = dwc2_exit_hibernation(hsotg, true); @@ -347,6 +345,10 @@ static void dwc2_handle_session_req_intr(struct dwc2_hsotg *hsotg) static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg) { int ret; + + /* Clear interrupt */ + dwc2_writel(GINTSTS_WKUPINT, hsotg->regs + GINTSTS); + dev_dbg(hsotg->dev, "++Resume or Remote Wakeup Detected Interrupt++\n"); dev_dbg(hsotg->dev, "%s lxstate = %d\n", __func__, hsotg->lx_state); @@ -368,10 +370,9 @@ static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg) /* Change to L0 state */ hsotg->lx_state = DWC2_L0; } else { - if (hsotg->core_params->hibernation) { - dwc2_writel(GINTSTS_WKUPINT, hsotg->regs + GINTSTS); + if (hsotg->core_params->hibernation) return; - } + if (hsotg->lx_state != DWC2_L1) { u32 pcgcctl = dwc2_readl(hsotg->regs + PCGCTL); @@ -385,9 +386,6 @@ static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg) hsotg->lx_state = DWC2_L0; } } - - /* Clear interrupt */ - dwc2_writel(GINTSTS_WKUPINT, hsotg->regs + GINTSTS); } /* @@ -396,14 +394,14 @@ static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg) */ static void dwc2_handle_disconnect_intr(struct dwc2_hsotg *hsotg) { + dwc2_writel(GINTSTS_DISCONNINT, hsotg->regs + GINTSTS); + dev_dbg(hsotg->dev, "++Disconnect Detected Interrupt++ (%s) %s\n", dwc2_is_host_mode(hsotg) ? "Host" : "Device", dwc2_op_state_str(hsotg)); if (hsotg->op_state == OTG_STATE_A_HOST) dwc2_hcd_disconnect(hsotg, false); - - dwc2_writel(GINTSTS_DISCONNINT, hsotg->regs + GINTSTS); } /* @@ -419,6 +417,9 @@ static void dwc2_handle_usb_suspend_intr(struct dwc2_hsotg *hsotg) u32 dsts; int ret; + /* Clear interrupt */ + dwc2_writel(GINTSTS_USBSUSP, hsotg->regs + GINTSTS); + dev_dbg(hsotg->dev, "USB SUSPEND\n"); if (dwc2_is_device_mode(hsotg)) { @@ -437,7 +438,7 @@ static void dwc2_handle_usb_suspend_intr(struct dwc2_hsotg *hsotg) if (!dwc2_is_device_connected(hsotg)) { dev_dbg(hsotg->dev, "ignore suspend request before enumeration\n"); - goto clear_int; + return; } ret = dwc2_enter_hibernation(hsotg); @@ -476,10 +477,6 @@ skip_power_saving: hsotg->op_state = OTG_STATE_A_HOST; } } - -clear_int: - /* Clear interrupt */ - dwc2_writel(GINTSTS_USBSUSP, hsotg->regs + GINTSTS); } #define GINTMSK_COMMON (GINTSTS_WKUPINT | GINTSTS_SESSREQINT | \ diff --git a/drivers/usb/dwc2/hcd_intr.c b/drivers/usb/dwc2/hcd_intr.c index a1eb48e54858..f8253803a050 100644 --- a/drivers/usb/dwc2/hcd_intr.c +++ b/drivers/usb/dwc2/hcd_intr.c @@ -122,6 +122,9 @@ static void dwc2_sof_intr(struct dwc2_hsotg *hsotg) struct dwc2_qh *qh; enum dwc2_transaction_type tr_type; + /* Clear interrupt */ + dwc2_writel(GINTSTS_SOF, hsotg->regs + GINTSTS); + #ifdef DEBUG_SOF dev_vdbg(hsotg->dev, "--Start of Frame Interrupt--\n"); #endif @@ -146,9 +149,6 @@ static void dwc2_sof_intr(struct dwc2_hsotg *hsotg) tr_type = dwc2_hcd_select_transactions(hsotg); if (tr_type != DWC2_TRANSACTION_NONE) dwc2_hcd_queue_transactions(hsotg, tr_type); - - /* Clear interrupt */ - dwc2_writel(GINTSTS_SOF, hsotg->regs + GINTSTS); } /* @@ -312,6 +312,7 @@ static void dwc2_hprt0_enable(struct dwc2_hsotg *hsotg, u32 hprt0, if (do_reset) { *hprt0_modify |= HPRT0_RST; + dwc2_writel(*hprt0_modify, hsotg->regs + HPRT0); queue_delayed_work(hsotg->wq_otg, &hsotg->reset_work, msecs_to_jiffies(60)); } else { @@ -347,11 +348,12 @@ static void dwc2_port_intr(struct dwc2_hsotg *hsotg) * Set flag and clear if detected */ if (hprt0 & HPRT0_CONNDET) { + dwc2_writel(hprt0_modify | HPRT0_CONNDET, hsotg->regs + HPRT0); + dev_vdbg(hsotg->dev, "--Port Interrupt HPRT0=0x%08x Port Connect Detected--\n", hprt0); dwc2_hcd_connect(hsotg); - hprt0_modify |= HPRT0_CONNDET; /* * The Hub driver asserts a reset when it sees port connect @@ -364,10 +366,10 @@ static void dwc2_port_intr(struct dwc2_hsotg *hsotg) * Clear if detected - Set internal flag if disabled */ if (hprt0 & HPRT0_ENACHG) { + dwc2_writel(hprt0_modify | HPRT0_ENACHG, hsotg->regs + HPRT0); dev_vdbg(hsotg->dev, " --Port Interrupt HPRT0=0x%08x Port Enable Changed (now %d)--\n", hprt0, !!(hprt0 & HPRT0_ENA)); - hprt0_modify |= HPRT0_ENACHG; if (hprt0 & HPRT0_ENA) { hsotg->new_connection = true; dwc2_hprt0_enable(hsotg, hprt0, &hprt0_modify); @@ -387,15 +389,13 @@ static void dwc2_port_intr(struct dwc2_hsotg *hsotg) /* Overcurrent Change Interrupt */ if (hprt0 & HPRT0_OVRCURRCHG) { + dwc2_writel(hprt0_modify | HPRT0_OVRCURRCHG, + hsotg->regs + HPRT0); dev_vdbg(hsotg->dev, " --Port Interrupt HPRT0=0x%08x Port Overcurrent Changed--\n", hprt0); hsotg->flags.b.port_over_current_change = 1; - hprt0_modify |= HPRT0_OVRCURRCHG; } - - /* Clear Port Interrupts */ - dwc2_writel(hprt0_modify, hsotg->regs + HPRT0); } /*
In general it is wise to clear interrupts before processing them. If you don't do that, you can get: 1. Interrupt happens 2. You look at system state and process interrupt 3. A new interrupt happens 4. You clear interrupt without processing it. This patch was actually a first attempt to fix missing device insertions as described in (usb: dwc2: host: Fix missing device insertions) and it did solve some of the signal bouncing problems but not all of them (which is why I submitted the other patch). Specifically, this patch itself would sometimes change: 1. hardware sees connect 2. hardware sees disconnect 3. hardware sees connect 4. dwc2_port_intr() - clears connect interrupt 5. dwc2_handle_common_intr() - calls dwc2_hcd_disconnect() ...to: 1. hardware sees connect 2. hardware sees disconnect 3. dwc2_port_intr() - clears connect interrupt 4. hardware sees connect 5. dwc2_handle_common_intr() - calls dwc2_hcd_disconnect() ...but with different timing then sometimes we'd still miss cable insertions. In any case, though this patch doesn't fix any (known) problems, it still seems wise as a general policy to clear interrupt before handling them. Note that for dwc2_handle_usb_port_intr(), instead of moving the clear of PRTINT to the beginning of the function we remove it completely. The only way to clear PRTINT is to clear the sources that set it in the first place. Signed-off-by: Douglas Anderson <dianders@chromium.org> --- Changes in v5: - Rebased upon testing/next from 15-11-20. - Fixed missing reset as found by code inspection during rebase. - Now atop fix for missing spinlock in reset. - Dropped John Youn's ack / tested by since there's a bugfix now. Changes in v4: - Don't replace dwc2_writel with writel (Antti Seppälä). - Update description to explain why we remove PRTINT clear. Changes in v3: - Don't (uselessly) clear the PRTINT anymore (Felipe Balbi). drivers/usb/dwc2/core_intr.c | 49 +++++++++++++++++++++----------------------- drivers/usb/dwc2/hcd_intr.c | 18 ++++++++-------- 2 files changed, 32 insertions(+), 35 deletions(-)