RE: [PATCH 2/2] usb: dwc3: Add workaround for host mode VBUS glitch when boot
Hi Felipe,
Sorry for the late response, I didn't receive your mail.
Felipe Balbi wrotes:
>Hi,
>
>Ran Wang writes:
>> +static void dwc3_power_off_all_roothub_ports(struct dwc3 *dwc)
>> +{
>> +int i, port_num;
>> +u32 reg, op_regs_base, offset;
>> +void __iomem*xhci_regs;
>> +
>> +/* xhci regs is not mapped yet, do it temperary here */
>> +if (dwc->xhci_resources[0].start) {
>> +xhci_regs = ioremap(dwc->xhci_resources[0].start,
>> +DWC3_XHCI_REGS_END);
>> +if (IS_ERR(xhci_regs)) {
>> +dev_err(dwc->dev, "Failed to ioremap xhci_regs\n");
>> +return;
>> +}
>> +
>> +op_regs_base = HC_LENGTH(readl(xhci_regs));
>> +reg = readl(xhci_regs + XHCI_HCSPARAMS1);
>> +port_num = HCS_MAX_PORTS(reg);
>> +
>> +for (i = 1; i <= port_num; i++) {
>> +offset = op_regs_base + XHCI_PORTSC_BASE + 0x10*(i-1);
>> +reg = readl(xhci_regs + offset);
>> +reg &= ~PORT_POWER;
>> +writel(reg, xhci_regs + offset);
>> +}
>> +
>> +iounmap(xhci_regs);
>
>why can't this be done during xhci_gen_setup()?
Actually I have done experiment like what you suggested (in xhci-plat.c), but
the timing
seems too late--making VBUS waveform look like a square wave as below:
Here DWC3 enable host mode, VBUS on
|
+5V /-\ 40ms /---
0V / 90ms \__/
| |
| Here do xhci reset, VBUS back to +5V again
Here set all PORTSC[PP] to 0 in xhci_gen_setup()
So I am afraid the solution might have to be added in DWC3 core driver where
just after host mode enabling code if want fix this :(
Regards,
Ran
Re: [PATCH 2/2] usb: dwc3: Add workaround for host mode VBUS glitch when boot
Hi Ran, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on usb/usb-testing] [also build test WARNING on v5.0-rc2 next-20190116] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] url: https://github.com/0day-ci/linux/commits/Ran-Wang/usb-dwc3-Add-avoiding-vbus-glitch-happen-during-xhci-reset/20190116-153950 base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing reproduce: make htmldocs All warnings (new ones prefixed by >>): WARNING: convert(1) not found, for SVG to PDF conversion install ImageMagick (https://www.imagemagick.org) include/linux/interrupt.h:268: warning: Function parameter or member 'is_managed' not described in 'irq_affinity_desc' include/linux/rcupdate_wait.h:1: warning: no structured comments found include/linux/rcutree.h:1: warning: no structured comments found kernel/rcu/tree.c:710: warning: Excess function parameter 'irq' description in 'rcu_nmi_exit' include/linux/gfp.h:1: warning: no structured comments found include/net/cfg80211.h:4687: warning: Function parameter or member 'wext.ibss' not described in 'wireless_dev' include/net/cfg80211.h:4687: warning: Function parameter or member 'wext.connect' not described in 'wireless_dev' include/net/cfg80211.h:4687: warning: Function parameter or member 'wext.keys' not described in 'wireless_dev' include/net/cfg80211.h:4687: warning: Function parameter or member 'wext.ie' not described in 'wireless_dev' include/net/cfg80211.h:4687: warning: Function parameter or member 'wext.ie_len' not described in 'wireless_dev' include/net/cfg80211.h:4687: warning: Function parameter or member 'wext.bssid' not described in 'wireless_dev' include/net/cfg80211.h:4687: warning: Function parameter or member 'wext.ssid' not described in 'wireless_dev' include/net/cfg80211.h:4687: warning: Function parameter or member 'wext.default_key' not described in 'wireless_dev' include/net/cfg80211.h:4687: warning: Function parameter or member 'wext.default_mgmt_key' not described in 'wireless_dev' include/net/cfg80211.h:4687: warning: Function parameter or member 'wext.prev_bssid_valid' not described in 'wireless_dev' include/net/mac80211.h:2393: warning: Function parameter or member 'radiotap_timestamp.units_pos' not described in 'ieee80211_hw' include/net/mac80211.h:2393: warning: Function parameter or member 'radiotap_timestamp.accuracy' not described in 'ieee80211_hw' include/net/mac80211.h:1004: warning: Function parameter or member 'control.rates' not described in 'ieee80211_tx_info' include/net/mac80211.h:1004: warning: Function parameter or member 'control.rts_cts_rate_idx' not described in 'ieee80211_tx_info' include/net/mac80211.h:1004: warning: Function parameter or member 'control.use_rts' not described in 'ieee80211_tx_info' include/net/mac80211.h:1004: warning: Function parameter or member 'control.use_cts_prot' not described in 'ieee80211_tx_info' include/net/mac80211.h:1004: warning: Function parameter or member 'control.short_preamble' not described in 'ieee80211_tx_info' include/net/mac80211.h:1004: warning: Function parameter or member 'control.skip_table' not described in 'ieee80211_tx_info' include/net/mac80211.h:1004: warning: Function parameter or member 'control.jiffies' not described in 'ieee80211_tx_info' include/net/mac80211.h:1004: warning: Function parameter or member 'control.vif' not described in 'ieee80211_tx_info' include/net/mac80211.h:1004: warning: Function parameter or member 'control.hw_key' not described in 'ieee80211_tx_info' include/net/mac80211.h:1004: warning: Function parameter or member 'control.flags' not described in 'ieee80211_tx_info' include/net/mac80211.h:1004: warning: Function parameter or member 'control.enqueue_time' not described in 'ieee80211_tx_info' include/net/mac80211.h:1004: warning: Function parameter or member 'ack' not described in 'ieee80211_tx_info' include/net/mac80211.h:1004: warning: Function parameter or member 'ack.cookie' not described in 'ieee80211_tx_info' include/net/mac80211.h:1004: warning: Function parameter or member 'status.rates' not described in 'ieee80211_tx_info' include/net/mac80211.h:1004: warning: Function parameter or member 'status.ack_signal' not described in 'ieee80211_tx_info' include/net/mac80211.h:1004: warning: Function parameter or member 'status.ampdu_ack_len' not described in 'ieee80211_tx_info' include/net/mac80211.h:1004: warning: Function parameter or member 'status.ampdu_len' not described in 'ieee80211_tx_info' include/net/mac80211.h:1004: warning: Function parameter or member 'status.antenna' not described in 'ieee80211_tx_info' include/net/mac80211.h:1004: warning: Function parameter or member 'status.tx_time' not described in 'ieee80211_tx_info' include/net/mac80211.h:1004: warning: Function parameter o
Re: [PATCH 2/2] usb: dwc3: Add workaround for host mode VBUS glitch when boot
Hi,
Ran Wang writes:
> +static void dwc3_power_off_all_roothub_ports(struct dwc3 *dwc)
> +{
> + int i, port_num;
> + u32 reg, op_regs_base, offset;
> + void __iomem*xhci_regs;
> +
> + /* xhci regs is not mapped yet, do it temperary here */
> + if (dwc->xhci_resources[0].start) {
> + xhci_regs = ioremap(dwc->xhci_resources[0].start,
> + DWC3_XHCI_REGS_END);
> + if (IS_ERR(xhci_regs)) {
> + dev_err(dwc->dev, "Failed to ioremap xhci_regs\n");
> + return;
> + }
> +
> + op_regs_base = HC_LENGTH(readl(xhci_regs));
> + reg = readl(xhci_regs + XHCI_HCSPARAMS1);
> + port_num = HCS_MAX_PORTS(reg);
> +
> + for (i = 1; i <= port_num; i++) {
> + offset = op_regs_base + XHCI_PORTSC_BASE + 0x10*(i-1);
> + reg = readl(xhci_regs + offset);
> + reg &= ~PORT_POWER;
> + writel(reg, xhci_regs + offset);
> + }
> +
> + iounmap(xhci_regs);
why can't this be done during xhci_gen_setup()?
--
balbi
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[PATCH 2/2] usb: dwc3: Add workaround for host mode VBUS glitch when boot
When DWC3 is set to host mode by programming register DWC3_GCTL, VUBS
(or its control signal) will be turned on immediately on related Root Hub
ports. Then, the VUBS is turned off for a little while(15us) when do xhci
reset (conducted by xhci driver) and back to normal finally, we can
observed a negative glitch of related signal from scope.
This VBUS glitch might cause some USB devices enumeration fail if kernel
boot with them connected. Such as LS1012AFWRY/LS1043ARDB/LX2160AQDS
/LS1088ARDB with Kingston 16GB USB2.0/Kingston USB3.0/JetFlash Transcend
4GB USB2.0 drives. The fail cases include enumerated as full-speed device
or report wrong device descriptor, etc.
One SW workaround which can fix this is to program all xhci PORTSC[PP]
to 0 to turn off VBUS immediately after setting host mode in DWC3 driver
(per signal measurement result, it will be too late to do it in
xhci-plat.c or xhci.c). Then, after xhci reset complete in xhci driver,
PORTSC[PP]s' value will back to 1 automatically and VBUS on at that time,
no glitch happen and normal enumeration process has no impact.
Signed-off-by: Ran Wang
---
drivers/usb/dwc3/core.c | 47 +++
drivers/usb/dwc3/core.h | 10 +-
2 files changed, 56 insertions(+), 1 deletions(-)
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index a1b126f..1508397 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -100,6 +100,41 @@ static int dwc3_get_dr_mode(struct dwc3 *dwc)
return 0;
}
+/*
+ * dwc3_power_of_all_roothub_ports - Power off all Root hub ports
+ * @dwc3: Pointer to our controller context structure
+ */
+static void dwc3_power_off_all_roothub_ports(struct dwc3 *dwc)
+{
+ int i, port_num;
+ u32 reg, op_regs_base, offset;
+ void __iomem*xhci_regs;
+
+ /* xhci regs is not mapped yet, do it temperary here */
+ if (dwc->xhci_resources[0].start) {
+ xhci_regs = ioremap(dwc->xhci_resources[0].start,
+ DWC3_XHCI_REGS_END);
+ if (IS_ERR(xhci_regs)) {
+ dev_err(dwc->dev, "Failed to ioremap xhci_regs\n");
+ return;
+ }
+
+ op_regs_base = HC_LENGTH(readl(xhci_regs));
+ reg = readl(xhci_regs + XHCI_HCSPARAMS1);
+ port_num = HCS_MAX_PORTS(reg);
+
+ for (i = 1; i <= port_num; i++) {
+ offset = op_regs_base + XHCI_PORTSC_BASE + 0x10*(i-1);
+ reg = readl(xhci_regs + offset);
+ reg &= ~PORT_POWER;
+ writel(reg, xhci_regs + offset);
+ }
+
+ iounmap(xhci_regs);
+ } else
+ dev_err(dwc->dev, "xhci base reg invalid\n");
+}
+
void dwc3_set_prtcap(struct dwc3 *dwc, u32 mode)
{
u32 reg;
@@ -109,6 +144,15 @@ void dwc3_set_prtcap(struct dwc3 *dwc, u32 mode)
reg |= DWC3_GCTL_PRTCAPDIR(mode);
dwc3_writel(dwc->regs, DWC3_GCTL, reg);
+ /*
+* We have to power off all Root hub ports immediately after DWC3 set
+* to host mode to avoid VBUS glitch happen when xhci get reset later.
+*/
+ if (dwc->avoid_vbus_glitch_when_set_host) {
+ if (mode == DWC3_GCTL_PRTCAP_HOST)
+ dwc3_power_off_all_roothub_ports(dwc);
+ }
+
dwc->current_dr_role = mode;
}
@@ -1306,6 +1350,9 @@ static void dwc3_get_properties(struct dwc3 *dwc)
dwc->dis_metastability_quirk = device_property_read_bool(dev,
"snps,dis_metastability_quirk");
+ dwc->avoid_vbus_glitch_when_set_host = device_property_read_bool(dev,
+ "snps,avoid-vbus-glitch-when-set-host");
+
dwc->lpm_nyet_threshold = lpm_nyet_threshold;
dwc->tx_de_emphasis = tx_de_emphasis;
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index df87641..691093b 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -606,6 +606,14 @@
#define DWC3_OSTS_VBUSVLD BIT(1)
#define DWC3_OSTS_CONIDSTS BIT(0)
+/* Partial XHCI Register and Bit fields for quirk */
+#define XHCI_HCSPARAMS10x4
+#define XHCI_PORTSC_BASE 0x400
+#define PORT_POWER (1 << 9)
+#define HCS_MAX_PORTS(p) (((p) >> 24) & 0x7f)
+#define XHCI_HC_LENGTH(p) (((p)>>00)&0x00ff)
+#define HC_LENGTH(p) XHCI_HC_LENGTH(p)
+
/* Structures */
struct dwc3_trb;
@@ -1209,6 +1217,7 @@ struct dwc3 {
unsignedtx_de_emphasis:2;
unsigneddis_metastability_quirk:1;
+ unsignedavoid_vbus_glitch_when_set_host:1;
u16 imod_interval;
};
@@ -1217,7 +1226,6 @@ struct dwc3 {
#define INCRX_UNDEF_LENGTH_BURST_MODE 1
#define work_to_dwc(w) (container_of((w), struct dwc3, drd_work))
