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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-18 17:35:05 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-18 17:39:31 +0000
commit85c675d0d09a45a135bddd15d7b385f8758c32fb (patch)
tree76267dbc9b9a130337be3640948fe397b04ac629 /drivers/usb/host/xhci-mtk-sch.c
parentAdding upstream version 6.6.15. (diff)
downloadlinux-85c675d0d09a45a135bddd15d7b385f8758c32fb.tar.xz
linux-85c675d0d09a45a135bddd15d7b385f8758c32fb.zip
Adding upstream version 6.7.7.upstream/6.7.7
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/usb/host/xhci-mtk-sch.c')
-rw-r--r--drivers/usb/host/xhci-mtk-sch.c411
1 files changed, 350 insertions, 61 deletions
diff --git a/drivers/usb/host/xhci-mtk-sch.c b/drivers/usb/host/xhci-mtk-sch.c
index 579899eb24..61f3f8bbdc 100644
--- a/drivers/usb/host/xhci-mtk-sch.c
+++ b/drivers/usb/host/xhci-mtk-sch.c
@@ -19,6 +19,18 @@
#define HS_BW_BOUNDARY 6144
/* usb2 spec section11.18.1: at most 188 FS bytes per microframe */
#define FS_PAYLOAD_MAX 188
+#define LS_PAYLOAD_MAX 18
+/* section 11.18.1, per fs frame */
+#define FS_BW_BOUNDARY 1157
+#define LS_BW_BOUNDARY 144
+
+/*
+ * max number of microframes for split transfer, assume extra-cs budget is 0
+ * for fs isoc in : 1 ss + 1 idle + 6 cs (roundup(1023/188))
+ */
+#define TT_MICROFRAMES_MAX 8
+/* offset from SS for fs/ls isoc/intr ep (ss + idle) */
+#define CS_OFFSET 2
#define DBG_BUF_EN 64
@@ -237,17 +249,26 @@ static void drop_tt(struct usb_device *udev)
static struct mu3h_sch_ep_info *
create_sch_ep(struct xhci_hcd_mtk *mtk, struct usb_device *udev,
- struct usb_host_endpoint *ep)
+ struct usb_host_endpoint *ep, struct xhci_ep_ctx *ep_ctx)
{
struct mu3h_sch_ep_info *sch_ep;
struct mu3h_sch_bw_info *bw_info;
struct mu3h_sch_tt *tt = NULL;
+ u32 len;
bw_info = get_bw_info(mtk, udev, ep);
if (!bw_info)
return ERR_PTR(-ENODEV);
- sch_ep = kzalloc(sizeof(*sch_ep), GFP_KERNEL);
+ if (is_fs_or_ls(udev->speed))
+ len = TT_MICROFRAMES_MAX;
+ else if ((udev->speed >= USB_SPEED_SUPER) &&
+ usb_endpoint_xfer_isoc(&ep->desc))
+ len = get_esit(ep_ctx);
+ else
+ len = 1;
+
+ sch_ep = kzalloc(struct_size(sch_ep, bw_budget_table, len), GFP_KERNEL);
if (!sch_ep)
return ERR_PTR(-ENOMEM);
@@ -279,7 +300,11 @@ static void setup_sch_info(struct xhci_ep_ctx *ep_ctx,
u32 mult;
u32 esit_pkts;
u32 max_esit_payload;
+ u32 bw_per_microframe;
+ u32 *bwb_table;
+ int i;
+ bwb_table = sch_ep->bw_budget_table;
ep_type = CTX_TO_EP_TYPE(le32_to_cpu(ep_ctx->ep_info2));
maxpkt = MAX_PACKET_DECODED(le32_to_cpu(ep_ctx->ep_info2));
max_burst = CTX_TO_MAX_BURST(le32_to_cpu(ep_ctx->ep_info2));
@@ -313,7 +338,7 @@ static void setup_sch_info(struct xhci_ep_ctx *ep_ctx,
* opportunities per microframe
*/
sch_ep->pkts = max_burst + 1;
- sch_ep->bw_cost_per_microframe = maxpkt * sch_ep->pkts;
+ bwb_table[0] = maxpkt * sch_ep->pkts;
} else if (sch_ep->speed >= USB_SPEED_SUPER) {
/* usb3_r1 spec section4.4.7 & 4.4.8 */
sch_ep->cs_count = 0;
@@ -330,6 +355,7 @@ static void setup_sch_info(struct xhci_ep_ctx *ep_ctx,
if (ep_type == INT_IN_EP || ep_type == INT_OUT_EP) {
sch_ep->pkts = esit_pkts;
sch_ep->num_budget_microframes = 1;
+ bwb_table[0] = maxpkt * sch_ep->pkts;
}
if (ep_type == ISOC_IN_EP || ep_type == ISOC_OUT_EP) {
@@ -346,18 +372,52 @@ static void setup_sch_info(struct xhci_ep_ctx *ep_ctx,
DIV_ROUND_UP(esit_pkts, sch_ep->pkts);
sch_ep->repeat = !!(sch_ep->num_budget_microframes > 1);
+ bw_per_microframe = maxpkt * sch_ep->pkts;
+
+ for (i = 0; i < sch_ep->num_budget_microframes - 1; i++)
+ bwb_table[i] = bw_per_microframe;
+
+ /* last one <= bw_per_microframe */
+ bwb_table[i] = maxpkt * esit_pkts - i * bw_per_microframe;
}
- sch_ep->bw_cost_per_microframe = maxpkt * sch_ep->pkts;
} else if (is_fs_or_ls(sch_ep->speed)) {
sch_ep->pkts = 1; /* at most one packet for each microframe */
/*
- * num_budget_microframes and cs_count will be updated when
+ * @cs_count will be updated to add extra-cs when
* check TT for INT_OUT_EP, ISOC/INT_IN_EP type
+ * @maxpkt <= 1023;
*/
sch_ep->cs_count = DIV_ROUND_UP(maxpkt, FS_PAYLOAD_MAX);
sch_ep->num_budget_microframes = sch_ep->cs_count;
- sch_ep->bw_cost_per_microframe = min_t(u32, maxpkt, FS_PAYLOAD_MAX);
+
+ /* init budget table */
+ if (ep_type == ISOC_OUT_EP) {
+ for (i = 0; i < sch_ep->cs_count - 1; i++)
+ bwb_table[i] = FS_PAYLOAD_MAX;
+
+ bwb_table[i] = maxpkt - i * FS_PAYLOAD_MAX;
+ } else if (ep_type == INT_OUT_EP) {
+ /* only first one used (maxpkt <= 64), others zero */
+ bwb_table[0] = maxpkt;
+ } else { /* INT_IN_EP or ISOC_IN_EP */
+ bwb_table[0] = 0; /* start split */
+ bwb_table[1] = 0; /* idle */
+ /*
+ * @cs_count will be updated according to cs position
+ * (add 1 or 2 extra-cs), but assume only first
+ * @num_budget_microframes elements will be used later,
+ * although in fact it does not (extra-cs budget many receive
+ * some data for IN ep);
+ * @cs_count is 1 for INT_IN_EP (maxpkt <= 64);
+ */
+ for (i = 0; i < sch_ep->cs_count - 1; i++)
+ bwb_table[i + CS_OFFSET] = FS_PAYLOAD_MAX;
+
+ bwb_table[i + CS_OFFSET] = maxpkt - i * FS_PAYLOAD_MAX;
+ /* ss + idle */
+ sch_ep->num_budget_microframes += CS_OFFSET;
+ }
}
}
@@ -374,7 +434,7 @@ static u32 get_max_bw(struct mu3h_sch_bw_info *sch_bw,
for (j = 0; j < sch_ep->num_budget_microframes; j++) {
k = XHCI_MTK_BW_INDEX(base + j);
- bw = sch_bw->bus_bw[k] + sch_ep->bw_cost_per_microframe;
+ bw = sch_bw->bus_bw[k] + sch_ep->bw_budget_table[j];
if (bw > max_bw)
max_bw = bw;
}
@@ -382,56 +442,152 @@ static u32 get_max_bw(struct mu3h_sch_bw_info *sch_bw,
return max_bw;
}
+/*
+ * for OUT: get first SS consumed bw;
+ * for IN: get first CS consumed bw;
+ */
+static u16 get_fs_bw(struct mu3h_sch_ep_info *sch_ep, int offset)
+{
+ struct mu3h_sch_tt *tt = sch_ep->sch_tt;
+ u16 fs_bw;
+
+ if (sch_ep->ep_type == ISOC_OUT_EP || sch_ep->ep_type == INT_OUT_EP)
+ fs_bw = tt->fs_bus_bw_out[XHCI_MTK_BW_INDEX(offset)];
+ else /* skip ss + idle */
+ fs_bw = tt->fs_bus_bw_in[XHCI_MTK_BW_INDEX(offset + CS_OFFSET)];
+
+ return fs_bw;
+}
+
static void update_bus_bw(struct mu3h_sch_bw_info *sch_bw,
struct mu3h_sch_ep_info *sch_ep, bool used)
{
- int bw_updated;
u32 base;
- int i, j;
-
- bw_updated = sch_ep->bw_cost_per_microframe * (used ? 1 : -1);
+ int i, j, k;
for (i = 0; i < sch_ep->num_esit; i++) {
base = sch_ep->offset + i * sch_ep->esit;
- for (j = 0; j < sch_ep->num_budget_microframes; j++)
- sch_bw->bus_bw[XHCI_MTK_BW_INDEX(base + j)] += bw_updated;
+ for (j = 0; j < sch_ep->num_budget_microframes; j++) {
+ k = XHCI_MTK_BW_INDEX(base + j);
+ if (used)
+ sch_bw->bus_bw[k] += sch_ep->bw_budget_table[j];
+ else
+ sch_bw->bus_bw[k] -= sch_ep->bw_budget_table[j];
+ }
}
}
-static int check_fs_bus_bw(struct mu3h_sch_ep_info *sch_ep, int offset)
+static int check_ls_budget_microframes(struct mu3h_sch_ep_info *sch_ep, int offset)
+{
+ struct mu3h_sch_tt *tt = sch_ep->sch_tt;
+ int i;
+
+ if (sch_ep->speed != USB_SPEED_LOW)
+ return 0;
+
+ if (sch_ep->ep_type == INT_OUT_EP)
+ i = XHCI_MTK_BW_INDEX(offset);
+ else if (sch_ep->ep_type == INT_IN_EP)
+ i = XHCI_MTK_BW_INDEX(offset + CS_OFFSET); /* skip ss + idle */
+ else
+ return -EINVAL;
+
+ if (tt->ls_bus_bw[i] + sch_ep->maxpkt > LS_PAYLOAD_MAX)
+ return -ESCH_BW_OVERFLOW;
+
+ return 0;
+}
+
+static int check_fs_budget_microframes(struct mu3h_sch_ep_info *sch_ep, int offset)
{
struct mu3h_sch_tt *tt = sch_ep->sch_tt;
u32 tmp;
- int base;
+ int i, k;
+
+ /*
+ * for OUT eps, will transfer exactly assigned length of data,
+ * so can't allocate more than 188 bytes;
+ * but it's not for IN eps, usually it can't receive full
+ * 188 bytes in a uframe, if it not assign full 188 bytes,
+ * can add another one;
+ */
+ for (i = 0; i < sch_ep->num_budget_microframes; i++) {
+ k = XHCI_MTK_BW_INDEX(offset + i);
+ if (sch_ep->ep_type == ISOC_OUT_EP || sch_ep->ep_type == INT_OUT_EP)
+ tmp = tt->fs_bus_bw_out[k] + sch_ep->bw_budget_table[i];
+ else /* ep_type : ISOC IN / INTR IN */
+ tmp = tt->fs_bus_bw_in[k];
+
+ if (tmp > FS_PAYLOAD_MAX)
+ return -ESCH_BW_OVERFLOW;
+ }
+
+ return 0;
+}
+
+static int check_fs_budget_frames(struct mu3h_sch_ep_info *sch_ep, int offset)
+{
+ struct mu3h_sch_tt *tt = sch_ep->sch_tt;
+ u32 head, tail;
int i, j, k;
+ /* bugdet scheduled may cross at most two fs frames */
+ j = XHCI_MTK_BW_INDEX(offset) / UFRAMES_PER_FRAME;
+ k = XHCI_MTK_BW_INDEX(offset + sch_ep->num_budget_microframes - 1) / UFRAMES_PER_FRAME;
+
+ if (j != k) {
+ head = tt->fs_frame_bw[j];
+ tail = tt->fs_frame_bw[k];
+ } else {
+ head = tt->fs_frame_bw[j];
+ tail = 0;
+ }
+
+ j = roundup(offset, UFRAMES_PER_FRAME);
+ for (i = 0; i < sch_ep->num_budget_microframes; i++) {
+ if ((offset + i) < j)
+ head += sch_ep->bw_budget_table[i];
+ else
+ tail += sch_ep->bw_budget_table[i];
+ }
+
+ if (head > FS_BW_BOUNDARY || tail > FS_BW_BOUNDARY)
+ return -ESCH_BW_OVERFLOW;
+
+ return 0;
+}
+
+static int check_fs_bus_bw(struct mu3h_sch_ep_info *sch_ep, int offset)
+{
+ int i, base;
+ int ret = 0;
+
for (i = 0; i < sch_ep->num_esit; i++) {
base = offset + i * sch_ep->esit;
- /*
- * Compared with hs bus, no matter what ep type,
- * the hub will always delay one uframe to send data
- */
- for (j = 0; j < sch_ep->num_budget_microframes; j++) {
- k = XHCI_MTK_BW_INDEX(base + j);
- tmp = tt->fs_bus_bw[k] + sch_ep->bw_cost_per_microframe;
- if (tmp > FS_PAYLOAD_MAX)
- return -ESCH_BW_OVERFLOW;
- }
+ ret = check_ls_budget_microframes(sch_ep, base);
+ if (ret)
+ goto err;
+
+ ret = check_fs_budget_microframes(sch_ep, base);
+ if (ret)
+ goto err;
+
+ ret = check_fs_budget_frames(sch_ep, base);
+ if (ret)
+ goto err;
}
- return 0;
+err:
+ return ret;
}
-static int check_sch_tt(struct mu3h_sch_ep_info *sch_ep, u32 offset)
+static int check_ss_and_cs(struct mu3h_sch_ep_info *sch_ep, u32 offset)
{
u32 start_ss, last_ss;
u32 start_cs, last_cs;
- if (!sch_ep->sch_tt)
- return 0;
-
- start_ss = offset % 8;
+ start_ss = offset % UFRAMES_PER_FRAME;
if (sch_ep->ep_type == ISOC_OUT_EP) {
last_ss = start_ss + sch_ep->cs_count - 1;
@@ -444,6 +600,7 @@ static int check_sch_tt(struct mu3h_sch_ep_info *sch_ep, u32 offset)
return -ESCH_SS_Y6;
} else {
+ /* maxpkt <= 1023, cs <= 6 */
u32 cs_count = DIV_ROUND_UP(sch_ep->maxpkt, FS_PAYLOAD_MAX);
/*
@@ -454,44 +611,171 @@ static int check_sch_tt(struct mu3h_sch_ep_info *sch_ep, u32 offset)
return -ESCH_SS_Y6;
/* one uframe for ss + one uframe for idle */
- start_cs = (start_ss + 2) % 8;
+ start_cs = (start_ss + CS_OFFSET) % UFRAMES_PER_FRAME;
last_cs = start_cs + cs_count - 1;
-
if (last_cs > 7)
return -ESCH_CS_OVERFLOW;
+ /* add extra-cs */
+ cs_count += (last_cs == 7) ? 1 : 2;
if (cs_count > 7)
cs_count = 7; /* HW limit */
sch_ep->cs_count = cs_count;
- /* ss, idle are ignored */
- sch_ep->num_budget_microframes = cs_count;
- /*
- * if interval=1, maxp >752, num_budge_micoframe is larger
- * than sch_ep->esit, will overstep boundary
- */
- if (sch_ep->num_budget_microframes > sch_ep->esit)
- sch_ep->num_budget_microframes = sch_ep->esit;
}
+ return 0;
+}
+
+/*
+ * when isoc-out transfers 188 bytes in a uframe, and send isoc/intr's
+ * ss token in the uframe, may cause 'bit stuff error' in downstream
+ * port;
+ * when isoc-out transfer less than 188 bytes in a uframe, shall send
+ * isoc-in's ss after isoc-out's ss (but hw can't ensure the sequence,
+ * so just avoid overlap).
+ */
+static int check_isoc_ss_overlap(struct mu3h_sch_ep_info *sch_ep, u32 offset)
+{
+ struct mu3h_sch_tt *tt = sch_ep->sch_tt;
+ int base;
+ int i, j, k;
+
+ if (!tt)
+ return 0;
+
+ for (i = 0; i < sch_ep->num_esit; i++) {
+ base = offset + i * sch_ep->esit;
+
+ if (sch_ep->ep_type == ISOC_OUT_EP) {
+ for (j = 0; j < sch_ep->num_budget_microframes; j++) {
+ k = XHCI_MTK_BW_INDEX(base + j);
+ if (tt->in_ss_cnt[k])
+ return -ESCH_SS_OVERLAP;
+ }
+ } else if (sch_ep->ep_type == ISOC_IN_EP || sch_ep->ep_type == INT_IN_EP) {
+ k = XHCI_MTK_BW_INDEX(base);
+ /* only check IN's ss */
+ if (tt->fs_bus_bw_out[k])
+ return -ESCH_SS_OVERLAP;
+ }
+ }
+
+ return 0;
+}
+
+static int check_sch_tt_budget(struct mu3h_sch_ep_info *sch_ep, u32 offset)
+{
+ int ret;
+
+ ret = check_ss_and_cs(sch_ep, offset);
+ if (ret)
+ return ret;
+
+ ret = check_isoc_ss_overlap(sch_ep, offset);
+ if (ret)
+ return ret;
+
return check_fs_bus_bw(sch_ep, offset);
}
+/* allocate microframes in the ls/fs frame */
+static int alloc_sch_portion_of_frame(struct mu3h_sch_ep_info *sch_ep)
+{
+ struct mu3h_sch_bw_info *sch_bw = sch_ep->bw_info;
+ const u32 bw_boundary = get_bw_boundary(sch_ep->speed);
+ u32 bw_max, fs_bw_min;
+ u32 offset, offset_min;
+ u16 fs_bw;
+ int frames;
+ int i, j;
+ int ret;
+
+ frames = sch_ep->esit / UFRAMES_PER_FRAME;
+
+ for (i = 0; i < UFRAMES_PER_FRAME; i++) {
+ fs_bw_min = FS_PAYLOAD_MAX;
+ offset_min = XHCI_MTK_MAX_ESIT;
+
+ for (j = 0; j < frames; j++) {
+ offset = (i + j * UFRAMES_PER_FRAME) % sch_ep->esit;
+
+ ret = check_sch_tt_budget(sch_ep, offset);
+ if (ret)
+ continue;
+
+ /* check hs bw domain */
+ bw_max = get_max_bw(sch_bw, sch_ep, offset);
+ if (bw_max > bw_boundary) {
+ ret = -ESCH_BW_OVERFLOW;
+ continue;
+ }
+
+ /* use best-fit between frames */
+ fs_bw = get_fs_bw(sch_ep, offset);
+ if (fs_bw < fs_bw_min) {
+ fs_bw_min = fs_bw;
+ offset_min = offset;
+ }
+
+ if (!fs_bw_min)
+ break;
+ }
+
+ /* use first-fit between microframes in a frame */
+ if (offset_min < XHCI_MTK_MAX_ESIT)
+ break;
+ }
+
+ if (offset_min == XHCI_MTK_MAX_ESIT)
+ return -ESCH_BW_OVERFLOW;
+
+ sch_ep->offset = offset_min;
+
+ return 0;
+}
+
static void update_sch_tt(struct mu3h_sch_ep_info *sch_ep, bool used)
{
struct mu3h_sch_tt *tt = sch_ep->sch_tt;
- int bw_updated;
+ u16 *fs_bus_bw;
u32 base;
- int i, j;
+ int i, j, k, f;
- bw_updated = sch_ep->bw_cost_per_microframe * (used ? 1 : -1);
+ if (sch_ep->ep_type == ISOC_OUT_EP || sch_ep->ep_type == INT_OUT_EP)
+ fs_bus_bw = tt->fs_bus_bw_out;
+ else
+ fs_bus_bw = tt->fs_bus_bw_in;
for (i = 0; i < sch_ep->num_esit; i++) {
base = sch_ep->offset + i * sch_ep->esit;
- for (j = 0; j < sch_ep->num_budget_microframes; j++)
- tt->fs_bus_bw[XHCI_MTK_BW_INDEX(base + j)] += bw_updated;
+ for (j = 0; j < sch_ep->num_budget_microframes; j++) {
+ k = XHCI_MTK_BW_INDEX(base + j);
+ f = k / UFRAMES_PER_FRAME;
+ if (used) {
+ if (sch_ep->speed == USB_SPEED_LOW)
+ tt->ls_bus_bw[k] += (u8)sch_ep->bw_budget_table[j];
+
+ fs_bus_bw[k] += (u16)sch_ep->bw_budget_table[j];
+ tt->fs_frame_bw[f] += (u16)sch_ep->bw_budget_table[j];
+ } else {
+ if (sch_ep->speed == USB_SPEED_LOW)
+ tt->ls_bus_bw[k] -= (u8)sch_ep->bw_budget_table[j];
+
+ fs_bus_bw[k] -= (u16)sch_ep->bw_budget_table[j];
+ tt->fs_frame_bw[f] -= (u16)sch_ep->bw_budget_table[j];
+ }
+ }
+
+ if (sch_ep->ep_type == ISOC_IN_EP || sch_ep->ep_type == INT_IN_EP) {
+ k = XHCI_MTK_BW_INDEX(base);
+ if (used)
+ tt->in_ss_cnt[k]++;
+ else
+ tt->in_ss_cnt[k]--;
+ }
}
if (used)
@@ -513,7 +797,8 @@ static int load_ep_bw(struct mu3h_sch_bw_info *sch_bw,
return 0;
}
-static int check_sch_bw(struct mu3h_sch_ep_info *sch_ep)
+/* allocate microframes for hs/ss/ssp */
+static int alloc_sch_microframes(struct mu3h_sch_ep_info *sch_ep)
{
struct mu3h_sch_bw_info *sch_bw = sch_ep->bw_info;
const u32 bw_boundary = get_bw_boundary(sch_ep->speed);
@@ -521,16 +806,12 @@ static int check_sch_bw(struct mu3h_sch_ep_info *sch_ep)
u32 worst_bw;
u32 min_bw = ~0;
int min_index = -1;
- int ret = 0;
/*
* Search through all possible schedule microframes.
* and find a microframe where its worst bandwidth is minimum.
*/
for (offset = 0; offset < sch_ep->esit; offset++) {
- ret = check_sch_tt(sch_ep, offset);
- if (ret)
- continue;
worst_bw = get_max_bw(sch_bw, sch_ep, offset);
if (worst_bw > bw_boundary)
@@ -540,21 +821,29 @@ static int check_sch_bw(struct mu3h_sch_ep_info *sch_ep)
min_bw = worst_bw;
min_index = offset;
}
-
- /* use first-fit for LS/FS */
- if (sch_ep->sch_tt && min_index >= 0)
- break;
-
- if (min_bw == 0)
- break;
}
if (min_index < 0)
- return ret ? ret : -ESCH_BW_OVERFLOW;
+ return -ESCH_BW_OVERFLOW;
sch_ep->offset = min_index;
- return load_ep_bw(sch_bw, sch_ep, true);
+ return 0;
+}
+
+static int check_sch_bw(struct mu3h_sch_ep_info *sch_ep)
+{
+ int ret;
+
+ if (sch_ep->sch_tt)
+ ret = alloc_sch_portion_of_frame(sch_ep);
+ else
+ ret = alloc_sch_microframes(sch_ep);
+
+ if (ret)
+ return ret;
+
+ return load_ep_bw(sch_ep->bw_info, sch_ep, true);
}
static void destroy_sch_ep(struct xhci_hcd_mtk *mtk, struct usb_device *udev,
@@ -651,7 +940,7 @@ static int add_ep_quirk(struct usb_hcd *hcd, struct usb_device *udev,
xhci_dbg(xhci, "%s %s\n", __func__, decode_ep(ep, udev->speed));
- sch_ep = create_sch_ep(mtk, udev, ep);
+ sch_ep = create_sch_ep(mtk, udev, ep, ep_ctx);
if (IS_ERR_OR_NULL(sch_ep))
return -ENOMEM;