1 From cbe6a244c89bd8826dbf007f8d26d1859f03b381 Mon Sep 17 00:00:00 2001
2 From: Jonathan Bell <jonathan@raspberrypi.com>
3 Date: Mon, 13 Dec 2021 15:05:56 +0000
4 Subject: [PATCH] xhci: refactor out TRBS_PER_SEGMENT define in runtime
7 In anticipation of adjusting the number of utilised TRBs in a ring
8 segment, add trbs_per_seg to struct xhci_ring and use this instead
9 of a compile-time define.
11 Signed-off-by: Jonathan Bell <jonathan@raspberrypi.com>
13 drivers/usb/host/xhci-mem.c | 48 +++++++++++++++++++-----------------
14 drivers/usb/host/xhci-ring.c | 20 +++++++++------
15 drivers/usb/host/xhci.c | 6 ++---
16 drivers/usb/host/xhci.h | 1 +
17 4 files changed, 42 insertions(+), 33 deletions(-)
19 --- a/drivers/usb/host/xhci-mem.c
20 +++ b/drivers/usb/host/xhci-mem.c
21 @@ -98,6 +98,7 @@ static void xhci_free_segments_for_ring(
23 static void xhci_link_segments(struct xhci_segment *prev,
24 struct xhci_segment *next,
25 + unsigned int trbs_per_seg,
26 enum xhci_ring_type type, bool chain_links)
29 @@ -106,16 +107,16 @@ static void xhci_link_segments(struct xh
32 if (type != TYPE_EVENT) {
33 - prev->trbs[TRBS_PER_SEGMENT-1].link.segment_ptr =
34 + prev->trbs[trbs_per_seg - 1].link.segment_ptr =
35 cpu_to_le64(next->dma);
37 /* Set the last TRB in the segment to have a TRB type ID of Link TRB */
38 - val = le32_to_cpu(prev->trbs[TRBS_PER_SEGMENT-1].link.control);
39 + val = le32_to_cpu(prev->trbs[trbs_per_seg - 1].link.control);
40 val &= ~TRB_TYPE_BITMASK;
41 val |= TRB_TYPE(TRB_LINK);
44 - prev->trbs[TRBS_PER_SEGMENT-1].link.control = cpu_to_le32(val);
45 + prev->trbs[trbs_per_seg - 1].link.control = cpu_to_le32(val);
49 @@ -139,15 +140,17 @@ static void xhci_link_rings(struct xhci_
50 (xhci->quirks & XHCI_AMD_0x96_HOST)));
52 next = ring->enq_seg->next;
53 - xhci_link_segments(ring->enq_seg, first, ring->type, chain_links);
54 - xhci_link_segments(last, next, ring->type, chain_links);
55 + xhci_link_segments(ring->enq_seg, first, ring->trbs_per_seg,
56 + ring->type, chain_links);
57 + xhci_link_segments(last, next, ring->trbs_per_seg,
58 + ring->type, chain_links);
59 ring->num_segs += num_segs;
60 - ring->num_trbs_free += (TRBS_PER_SEGMENT - 1) * num_segs;
61 + ring->num_trbs_free += (ring->trbs_per_seg - 1) * num_segs;
63 if (ring->type != TYPE_EVENT && ring->enq_seg == ring->last_seg) {
64 - ring->last_seg->trbs[TRBS_PER_SEGMENT-1].link.control
65 + ring->last_seg->trbs[ring->trbs_per_seg - 1].link.control
66 &= ~cpu_to_le32(LINK_TOGGLE);
67 - last->trbs[TRBS_PER_SEGMENT-1].link.control
68 + last->trbs[ring->trbs_per_seg - 1].link.control
69 |= cpu_to_le32(LINK_TOGGLE);
70 ring->last_seg = last;
72 @@ -314,14 +317,15 @@ void xhci_initialize_ring_info(struct xh
73 * Each segment has a link TRB, and leave an extra TRB for SW
76 - ring->num_trbs_free = ring->num_segs * (TRBS_PER_SEGMENT - 1) - 1;
77 + ring->num_trbs_free = ring->num_segs * (ring->trbs_per_seg - 1) - 1;
80 /* Allocate segments and link them for a ring */
81 static int xhci_alloc_segments_for_ring(struct xhci_hcd *xhci,
82 struct xhci_segment **first, struct xhci_segment **last,
83 - unsigned int num_segs, unsigned int cycle_state,
84 - enum xhci_ring_type type, unsigned int max_packet, gfp_t flags)
85 + unsigned int num_segs, unsigned int trbs_per_seg,
86 + unsigned int cycle_state, enum xhci_ring_type type,
87 + unsigned int max_packet, gfp_t flags)
89 struct xhci_segment *prev;
91 @@ -350,12 +354,12 @@ static int xhci_alloc_segments_for_ring(
95 - xhci_link_segments(prev, next, type, chain_links);
96 + xhci_link_segments(prev, next, trbs_per_seg, type, chain_links);
101 - xhci_link_segments(prev, *first, type, chain_links);
102 + xhci_link_segments(prev, *first, trbs_per_seg, type, chain_links);
106 @@ -387,16 +391,17 @@ struct xhci_ring *xhci_ring_alloc(struct
110 + ring->trbs_per_seg = TRBS_PER_SEGMENT;
111 ret = xhci_alloc_segments_for_ring(xhci, &ring->first_seg,
112 - &ring->last_seg, num_segs, cycle_state, type,
113 - max_packet, flags);
114 + &ring->last_seg, num_segs, ring->trbs_per_seg,
115 + cycle_state, type, max_packet, flags);
119 /* Only event ring does not use link TRB */
120 if (type != TYPE_EVENT) {
121 /* See section 4.9.2.1 and 6.4.4.1 */
122 - ring->last_seg->trbs[TRBS_PER_SEGMENT - 1].link.control |=
123 + ring->last_seg->trbs[ring->trbs_per_seg - 1].link.control |=
124 cpu_to_le32(LINK_TOGGLE);
126 xhci_initialize_ring_info(ring, cycle_state);
127 @@ -429,16 +434,15 @@ int xhci_ring_expansion(struct xhci_hcd
128 unsigned int num_segs_needed;
131 - num_segs_needed = (num_trbs + (TRBS_PER_SEGMENT - 1) - 1) /
132 - (TRBS_PER_SEGMENT - 1);
134 + num_segs_needed = (num_trbs + (ring->trbs_per_seg - 1) - 1) /
135 + (ring->trbs_per_seg - 1);
136 /* Allocate number of segments we needed, or double the ring size */
137 num_segs = ring->num_segs > num_segs_needed ?
138 ring->num_segs : num_segs_needed;
140 ret = xhci_alloc_segments_for_ring(xhci, &first, &last,
141 - num_segs, ring->cycle_state, ring->type,
142 - ring->bounce_buf_len, flags);
143 + num_segs, ring->trbs_per_seg, ring->cycle_state,
144 + ring->type, ring->bounce_buf_len, flags);
148 @@ -1811,7 +1815,7 @@ int xhci_alloc_erst(struct xhci_hcd *xhc
149 for (val = 0; val < evt_ring->num_segs; val++) {
150 entry = &erst->entries[val];
151 entry->seg_addr = cpu_to_le64(seg->dma);
152 - entry->seg_size = cpu_to_le32(TRBS_PER_SEGMENT);
153 + entry->seg_size = cpu_to_le32(evt_ring->trbs_per_seg);
157 --- a/drivers/usb/host/xhci-ring.c
158 +++ b/drivers/usb/host/xhci-ring.c
159 @@ -90,15 +90,16 @@ static bool trb_is_link(union xhci_trb *
160 return TRB_TYPE_LINK_LE32(trb->link.control);
163 -static bool last_trb_on_seg(struct xhci_segment *seg, union xhci_trb *trb)
164 +static bool last_trb_on_seg(struct xhci_segment *seg,
165 + unsigned int trbs_per_seg, union xhci_trb *trb)
167 - return trb == &seg->trbs[TRBS_PER_SEGMENT - 1];
168 + return trb == &seg->trbs[trbs_per_seg - 1];
171 static bool last_trb_on_ring(struct xhci_ring *ring,
172 struct xhci_segment *seg, union xhci_trb *trb)
174 - return last_trb_on_seg(seg, trb) && (seg->next == ring->first_seg);
175 + return last_trb_on_seg(seg, ring->trbs_per_seg, trb) && (seg->next == ring->first_seg);
178 static bool link_trb_toggles_cycle(union xhci_trb *trb)
179 @@ -161,7 +162,8 @@ void inc_deq(struct xhci_hcd *xhci, stru
181 /* event ring doesn't have link trbs, check for last trb */
182 if (ring->type == TYPE_EVENT) {
183 - if (!last_trb_on_seg(ring->deq_seg, ring->dequeue)) {
184 + if (!last_trb_on_seg(ring->deq_seg, ring->trbs_per_seg,
189 @@ -174,7 +176,8 @@ void inc_deq(struct xhci_hcd *xhci, stru
191 /* All other rings have link trbs */
192 if (!trb_is_link(ring->dequeue)) {
193 - if (last_trb_on_seg(ring->deq_seg, ring->dequeue)) {
194 + if (last_trb_on_seg(ring->deq_seg, ring->trbs_per_seg,
196 xhci_warn(xhci, "Missing link TRB at end of segment\n");
199 @@ -225,7 +228,7 @@ static void inc_enq(struct xhci_hcd *xhc
200 if (!trb_is_link(ring->enqueue))
201 ring->num_trbs_free--;
203 - if (last_trb_on_seg(ring->enq_seg, ring->enqueue)) {
204 + if (last_trb_on_seg(ring->enq_seg, ring->trbs_per_seg, ring->enqueue)) {
205 xhci_err(xhci, "Tried to move enqueue past ring segment\n");
208 @@ -3153,7 +3156,7 @@ irqreturn_t xhci_irq(struct usb_hcd *hcd
209 * that clears the EHB.
211 while (xhci_handle_event(xhci) > 0) {
212 - if (event_loop++ < TRBS_PER_SEGMENT / 2)
213 + if (event_loop++ < xhci->event_ring->trbs_per_seg / 2)
215 xhci_update_erst_dequeue(xhci, event_ring_deq);
216 event_ring_deq = xhci->event_ring->dequeue;
217 @@ -3295,7 +3298,8 @@ static int prepare_ring(struct xhci_hcd
221 - if (last_trb_on_seg(ep_ring->enq_seg, ep_ring->enqueue)) {
222 + if (last_trb_on_seg(ep_ring->enq_seg, ep_ring->trbs_per_seg,
223 + ep_ring->enqueue)) {
224 xhci_warn(xhci, "Missing link TRB at end of ring segment\n");
227 --- a/drivers/usb/host/xhci.c
228 +++ b/drivers/usb/host/xhci.c
229 @@ -870,8 +870,8 @@ static void xhci_clear_command_ring(stru
233 - sizeof(union xhci_trb) * (TRBS_PER_SEGMENT - 1));
234 - seg->trbs[TRBS_PER_SEGMENT - 1].link.control &=
235 + sizeof(union xhci_trb) * (ring->trbs_per_seg - 1));
236 + seg->trbs[ring->trbs_per_seg - 1].link.control &=
237 cpu_to_le32(~TRB_CYCLE);
239 } while (seg != ring->deq_seg);
240 @@ -882,7 +882,7 @@ static void xhci_clear_command_ring(stru
241 ring->enq_seg = ring->deq_seg;
242 ring->enqueue = ring->dequeue;
244 - ring->num_trbs_free = ring->num_segs * (TRBS_PER_SEGMENT - 1) - 1;
245 + ring->num_trbs_free = ring->num_segs * (ring->trbs_per_seg - 1) - 1;
247 * Ring is now zeroed, so the HW should look for change of ownership
248 * when the cycle bit is set to 1.
249 --- a/drivers/usb/host/xhci.h
250 +++ b/drivers/usb/host/xhci.h
251 @@ -1635,6 +1635,7 @@ struct xhci_ring {
252 unsigned int num_trbs_free;
253 unsigned int num_trbs_free_temp;
254 unsigned int bounce_buf_len;
255 + unsigned int trbs_per_seg;
256 enum xhci_ring_type type;
257 bool last_td_was_short;
258 struct radix_tree_root *trb_address_map;