[RFC PATCH v3 1/5] usb: xhci-mtk: improve bandwidth scheduling with multi-TT

Chunfeng Yun
2020-12-22T09:36:02Z

From: Zhanyong Wang <zhanyong.wang@mediatek.com>

After inserted the usb type-c 3.5mm dongle with headset, dmesg showed:
usb 1-1.1: new full-speed USB device number 5 using xhci-mtk
usb 1-1.1: New USB device found, idVendor=05ac, idProduct=110a, bcdDevice=26.11
usb 1-1.1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
usb 1-1.1: Product: USB-C to 3.5mm Headphone Jack Adapter
usb 1-1.1: Manufacturer: Apple, Inc.
usb 1-1.1: SerialNumber: DWH915501TFJKLTAM
xhci-mtk 11200000.xhci: Not enough bandwidth!
usb 1-1.1: can't set config #2, error -28

improve low-speed/full-speed INT/ISOC bandwidth scheduling with USB
muli-TT.

Signed-off-by: Yaqii Wu <yaqii.wu@mediatek.com>
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
---
v2~v3: no changes
---
drivers/usb/host/xhci-mtk-sch.c | 91 ++++++++++++++++++++++++++++-----
drivers/usb/host/xhci-mtk.h | 8 ++-
2 files changed, 84 insertions(+), 15 deletions(-)
mode change 100644 => 100755 drivers/usb/host/xhci-mtk-sch.c

diff --git a/drivers/usb/host/xhci-mtk-sch.c b/drivers/usb/host/xhci-mtk-sch.c
old mode 100644
new mode 100755
index 45c54d56ecbd..94292b9bbc63
--- a/drivers/usb/host/xhci-mtk-sch.c
+++ b/drivers/usb/host/xhci-mtk-sch.c
@@ -383,7 +383,9 @@ static int check_sch_tt(struct usb_device *udev,
u32 fs_budget_start;
u32 start_ss, last_ss;
u32 start_cs, last_cs;
- int i;
+ u32 num_esit, base;
+ int i, j;
+ u32 tmp;

start_ss = offset % 8;
fs_budget_start = (start_ss + 1) % 8;
@@ -398,10 +400,13 @@ static int check_sch_tt(struct usb_device *udev,
if (!(start_ss == 7 || last_ss < 6))
return -ERANGE;

- for (i = 0; i < sch_ep->cs_count; i++)
- if (test_bit(offset + i, tt->split_bit_map))
+ for (i = 0; i < sch_ep->cs_count; i++) {
+ if (test_bit(offset + i, tt->ss_bit_map))
return -ERANGE;

+ if (test_bit(offset + i, tt->cs_bit_map))
+ return -ERANGE;
+ }
} else {
u32 cs_count = DIV_ROUND_UP(sch_ep->maxpkt, FS_PAYLOAD_MAX);

@@ -428,8 +433,10 @@ static int check_sch_tt(struct usb_device *udev,
if (cs_count > 7)
cs_count = 7; /* HW limit */

- for (i = 0; i < cs_count + 2; i++) {
- if (test_bit(offset + i, tt->split_bit_map))
+ if (test_bit(offset, tt->ss_bit_map))
+ return -ERANGE;
+ for (i = 0; i < cs_count; i++) {
+ if (test_bit(offset + 2 + i, tt->cs_bit_map))
return -ERANGE;
}

@@ -445,11 +452,22 @@ static int check_sch_tt(struct usb_device *udev,
sch_ep->num_budget_microframes = sch_ep->esit;
}

+ num_esit = XHCI_MTK_MAX_ESIT / sch_ep->esit;
+ for (i = 0; i < num_esit; i++) {
+ base = sch_ep->offset + i * sch_ep->esit;
+ for (j = 0; j < sch_ep->num_budget_microframes; j++) {
+ tmp = tt->fs_bus_bw[base + j]
+ + sch_ep->bw_cost_per_microframe;
+ if (tmp > FS_PAYLOAD_MAX)
+ return -ERANGE;
+ }
+ }
+
return 0;
}

static void update_sch_tt(struct usb_device *udev,
- struct mu3h_sch_ep_info *sch_ep)
+ struct mu3h_sch_ep_info *sch_ep, bool used)
{
struct mu3h_sch_tt *tt = sch_ep->sch_tt;
u32 base, num_esit;
@@ -458,11 +476,52 @@ static void update_sch_tt(struct usb_device *udev,
num_esit = XHCI_MTK_MAX_ESIT / sch_ep->esit;
for (i = 0; i < num_esit; i++) {
base = sch_ep->offset + i * sch_ep->esit;
- for (j = 0; j < sch_ep->num_budget_microframes; j++)
- set_bit(base + j, tt->split_bit_map);
+ for (j = 0; j < sch_ep->num_budget_microframes; j++) {
+ if (used)
+ set_bit(base + j, tt->split_bit_map);
+ else
+ clear_bit(base + j, tt->split_bit_map);
+ }
+
+ if (sch_ep->ep_type == ISOC_OUT_EP) {
+ for (j = 0; j < sch_ep->num_budget_microframes; j++) {
+ if (used) {
+ set_bit(base + j, tt->ss_bit_map);
+ set_bit(base + j, tt->cs_bit_map);
+ tt->fs_bus_bw[base + j] +=
+ sch_ep->bw_cost_per_microframe;
+ } else {
+ clear_bit(base + j, tt->ss_bit_map);
+ clear_bit(base + j, tt->cs_bit_map);
+ tt->fs_bus_bw[base + j] -=
+ sch_ep->bw_cost_per_microframe;
+ }
+ }
+ } else {
+ if (used)
+ set_bit(base, tt->ss_bit_map);
+ else
+ clear_bit(base, tt->ss_bit_map);
+
+ for (j = 0; j < sch_ep->cs_count; j++) {
+ if (used) {
+ set_bit(base + 2 + j, tt->cs_bit_map);
+
+ tt->fs_bus_bw[base + 2 + j] +=
+ sch_ep->bw_cost_per_microframe;
+ } else {
+ clear_bit(base + 2 + j, tt->cs_bit_map);
+ tt->fs_bus_bw[base + 2 + j] -=
+ sch_ep->bw_cost_per_microframe;
+ }
+ }
+ }
}

- list_add_tail(&sch_ep->tt_endpoint, &tt->ep_list);
+ if (used)
+ list_add_tail(&sch_ep->tt_endpoint, &tt->ep_list);
+ else
+ list_del(&sch_ep->tt_endpoint);
}

static int check_sch_bw(struct usb_device *udev,
@@ -470,6 +529,7 @@ static int check_sch_bw(struct usb_device *udev,
{
u32 offset;
u32 esit;
+ u32 boundary;
u32 min_bw;
u32 min_index;
u32 worst_bw;
@@ -487,10 +547,13 @@ static int check_sch_bw(struct usb_device *udev,
*/
min_bw = ~0;
min_index = 0;
+ boundary = esit;
min_cs_count = sch_ep->cs_count;
min_num_budget = sch_ep->num_budget_microframes;
for (offset = 0; offset < esit; offset++) {
if (is_fs_or_ls(udev->speed)) {
+ if (sch_ep->ep_type != ISOC_OUT_EP)
+ boundary = esit + 1;
ret = check_sch_tt(udev, sch_ep, offset);
if (ret)
continue;
@@ -498,7 +561,7 @@ static int check_sch_bw(struct usb_device *udev,
tt_offset_ok = true;
}

- if ((offset + sch_ep->num_budget_microframes) > sch_ep->esit)
+ if ((offset + sch_ep->num_budget_microframes) > boundary)
break;

worst_bw = get_max_bw(sch_bw, sch_ep, offset);
@@ -532,7 +595,7 @@ static int check_sch_bw(struct usb_device *udev,
if (!tt_offset_ok)
return -ERANGE;

- update_sch_tt(udev, sch_ep);
+ update_sch_tt(udev, sch_ep, 1);
}

/* update bus bandwidth info */
@@ -696,12 +759,12 @@ void xhci_mtk_drop_ep_quirk(struct usb_hcd *hcd, struct usb_device *udev,

list_for_each_entry(sch_ep, &sch_bw->bw_ep_list, endpoint) {
if (sch_ep->ep == ep) {
- update_bus_bw(sch_bw, sch_ep, 0);
- list_del(&sch_ep->endpoint);
if (is_fs_or_ls(udev->speed)) {
- list_del(&sch_ep->tt_endpoint);
+ update_sch_tt(udev, sch_ep, 0);
drop_tt(udev);
}
+ update_bus_bw(sch_bw, sch_ep, 0);
+ list_del(&sch_ep->endpoint);
kfree(sch_ep);
break;
}
diff --git a/drivers/usb/host/xhci-mtk.h b/drivers/usb/host/xhci-mtk.h
index a93cfe817904..323b281933b9 100644
--- a/drivers/usb/host/xhci-mtk.h
+++ b/drivers/usb/host/xhci-mtk.h
@@ -21,12 +21,18 @@

/**
* @split_bit_map: used to avoid split microframes overlay
+ * @ss_bit_map: used to avoid start split microframes overlay
+ * @cs_bit_map: used to avoid complete split microframes overlay
+ * @fs_bus_bw: array to keep track of bandwidth already used at full speed
* @ep_list: Endpoints using this TT
* @usb_tt: usb TT related
* @tt_port: TT port number
*/
struct mu3h_sch_tt {
DECLARE_BITMAP(split_bit_map, XHCI_MTK_MAX_ESIT);
+ DECLARE_BITMAP(ss_bit_map, XHCI_MTK_MAX_ESIT);
+ DECLARE_BITMAP(cs_bit_map, XHCI_MTK_MAX_ESIT + 1);
+ u32 fs_bus_bw[XHCI_MTK_MAX_ESIT];
struct list_head ep_list;
struct usb_tt *usb_tt;
int tt_port;
@@ -42,7 +48,7 @@ struct mu3h_sch_tt {
* two bandwidth domains, one for IN eps and another for OUT eps.
*/
struct mu3h_sch_bw_info {
- u32 bus_bw[XHCI_MTK_MAX_ESIT];
+ u32 bus_bw[XHCI_MTK_MAX_ESIT + 1];
struct list_head bw_ep_list;
};

--
2.18.0