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WIP FPC-III support
[linux/fpc-iii.git] / drivers / net / wireless / quantenna / qtnfmac / pcie / topaz_pcie.c
blob24f1be8ddcefb9bee6840edd3087c0809b81f4ef
1 // SPDX-License-Identifier: GPL-2.0+
2 /* Copyright (c) 2018 Quantenna Communications */
3
4 #include <linux/kernel.h>
5 #include <linux/firmware.h>
6 #include <linux/pci.h>
7 #include <linux/vmalloc.h>
8 #include <linux/delay.h>
9 #include <linux/interrupt.h>
10 #include <linux/sched.h>
11 #include <linux/crc32.h>
12 #include <linux/completion.h>
13 #include <linux/spinlock.h>
14 #include <linux/circ_buf.h>
15
16 #include "pcie_priv.h"
17 #include "topaz_pcie_regs.h"
18 #include "topaz_pcie_ipc.h"
19 #include "qtn_hw_ids.h"
20 #include "core.h"
21 #include "bus.h"
22 #include "shm_ipc.h"
23 #include "debug.h"
24
25 #define TOPAZ_TX_BD_SIZE_DEFAULT 128
26 #define TOPAZ_RX_BD_SIZE_DEFAULT 256
27
28 struct qtnf_topaz_tx_bd {
29 __le32 addr;
30 __le32 info;
31 } __packed;
32
33 struct qtnf_topaz_rx_bd {
34 __le32 addr;
35 __le32 info;
36 } __packed;
37
38 struct qtnf_extra_bd_params {
39 __le32 param1;
40 __le32 param2;
41 __le32 param3;
42 __le32 param4;
43 } __packed;
44
45 #define QTNF_BD_PARAM_OFFSET(n) offsetof(struct qtnf_extra_bd_params, param##n)
46
47 struct vmac_pkt_info {
48 __le32 addr;
49 __le32 info;
50 };
51
52 struct qtnf_topaz_bda {
53 __le16 bda_len;
54 __le16 bda_version;
55 __le32 bda_bootstate;
56 __le32 bda_dma_mask;
57 __le32 bda_dma_offset;
58 __le32 bda_flags;
59 __le32 bda_img;
60 __le32 bda_img_size;
61 __le32 bda_ep2h_irqstatus;
62 __le32 bda_h2ep_irqstatus;
63 __le32 bda_msi_addr;
64 u8 reserved1[56];
65 __le32 bda_flashsz;
66 u8 bda_boardname[PCIE_BDA_NAMELEN];
67 __le32 bda_pci_pre_status;
68 __le32 bda_pci_endian;
69 __le32 bda_pci_post_status;
70 __le32 bda_h2ep_txd_budget;
71 __le32 bda_ep2h_txd_budget;
72 __le32 bda_rc_rx_bd_base;
73 __le32 bda_rc_rx_bd_num;
74 __le32 bda_rc_tx_bd_base;
75 __le32 bda_rc_tx_bd_num;
76 u8 bda_ep_link_state;
77 u8 bda_rc_link_state;
78 u8 bda_rc_msi_enabled;
79 u8 reserved2;
80 __le32 bda_ep_next_pkt;
81 struct vmac_pkt_info request[QTN_PCIE_RC_TX_QUEUE_LEN];
82 struct qtnf_shm_ipc_region bda_shm_reg1 __aligned(4096);
83 struct qtnf_shm_ipc_region bda_shm_reg2 __aligned(4096);
84 } __packed;
85
86 struct qtnf_pcie_topaz_state {
87 struct qtnf_pcie_bus_priv base;
88 struct qtnf_topaz_bda __iomem *bda;
89
90 dma_addr_t dma_msi_dummy;
91 u32 dma_msi_imwr;
92
93 struct qtnf_topaz_tx_bd *tx_bd_vbase;
94 struct qtnf_topaz_rx_bd *rx_bd_vbase;
95
96 __le32 __iomem *ep_next_rx_pkt;
97 __le32 __iomem *txqueue_wake;
98 __le32 __iomem *ep_pmstate;
99
100 unsigned long rx_pkt_count;
101 };
102
103 static void qtnf_deassert_intx(struct qtnf_pcie_topaz_state *ts)
104 {
105 void __iomem *reg = ts->base.sysctl_bar + TOPAZ_PCIE_CFG0_OFFSET;
106 u32 cfg;
107
108 cfg = readl(reg);
109 cfg &= ~TOPAZ_ASSERT_INTX;
110 qtnf_non_posted_write(cfg, reg);
111 }
112
113 static inline int qtnf_topaz_intx_asserted(struct qtnf_pcie_topaz_state *ts)
114 {
115 void __iomem *reg = ts->base.sysctl_bar + TOPAZ_PCIE_CFG0_OFFSET;
116 u32 cfg = readl(reg);
117
118 return !!(cfg & TOPAZ_ASSERT_INTX);
119 }
120
121 static void qtnf_topaz_reset_ep(struct qtnf_pcie_topaz_state *ts)
122 {
123 writel(TOPAZ_IPC_IRQ_WORD(TOPAZ_RC_RST_EP_IRQ),
124 TOPAZ_LH_IPC4_INT(ts->base.sysctl_bar));
125 msleep(QTN_EP_RESET_WAIT_MS);
126 pci_restore_state(ts->base.pdev);
127 }
128
129 static void setup_rx_irqs(struct qtnf_pcie_topaz_state *ts)
130 {
131 void __iomem *reg = PCIE_DMA_WR_DONE_IMWR_ADDR_LOW(ts->base.dmareg_bar);
132
133 ts->dma_msi_imwr = readl(reg);
134 }
135
136 static void enable_rx_irqs(struct qtnf_pcie_topaz_state *ts)
137 {
138 void __iomem *reg = PCIE_DMA_WR_DONE_IMWR_ADDR_LOW(ts->base.dmareg_bar);
139
140 qtnf_non_posted_write(ts->dma_msi_imwr, reg);
141 }
142
143 static void disable_rx_irqs(struct qtnf_pcie_topaz_state *ts)
144 {
145 void __iomem *reg = PCIE_DMA_WR_DONE_IMWR_ADDR_LOW(ts->base.dmareg_bar);
146
147 qtnf_non_posted_write(QTN_HOST_LO32(ts->dma_msi_dummy), reg);
148 }
149
150 static void qtnf_topaz_ipc_gen_ep_int(void *arg)
151 {
152 struct qtnf_pcie_topaz_state *ts = arg;
153
154 writel(TOPAZ_IPC_IRQ_WORD(TOPAZ_RC_CTRL_IRQ),
155 TOPAZ_CTL_M2L_INT(ts->base.sysctl_bar));
156 }
157
158 static int qtnf_is_state(__le32 __iomem *reg, u32 state)
159 {
160 u32 s = readl(reg);
161
162 return (s == state);
163 }
164
165 static void qtnf_set_state(__le32 __iomem *reg, u32 state)
166 {
167 qtnf_non_posted_write(state, reg);
168 }
169
170 static int qtnf_poll_state(__le32 __iomem *reg, u32 state, u32 delay_in_ms)
171 {
172 u32 timeout = 0;
173
174 while ((qtnf_is_state(reg, state) == 0)) {
175 usleep_range(1000, 1200);
176 if (++timeout > delay_in_ms)
177 return -1;
178 }
179
180 return 0;
181 }
182
183 static int topaz_alloc_bd_table(struct qtnf_pcie_topaz_state *ts,
184 struct qtnf_topaz_bda __iomem *bda)
185 {
186 struct qtnf_extra_bd_params __iomem *extra_params;
187 struct qtnf_pcie_bus_priv *priv = &ts->base;
188 dma_addr_t paddr;
189 void *vaddr;
190 int len;
191 int i;
192
193 /* bd table */
194
195 len = priv->tx_bd_num * sizeof(struct qtnf_topaz_tx_bd) +
196 priv->rx_bd_num * sizeof(struct qtnf_topaz_rx_bd) +
197 sizeof(struct qtnf_extra_bd_params);
198
199 vaddr = dmam_alloc_coherent(&priv->pdev->dev, len, &paddr, GFP_KERNEL);
200 if (!vaddr)
201 return -ENOMEM;
202
203 /* tx bd */
204
205 ts->tx_bd_vbase = vaddr;
206 qtnf_non_posted_write(paddr, &bda->bda_rc_tx_bd_base);
207
208 for (i = 0; i < priv->tx_bd_num; i++)
209 ts->tx_bd_vbase[i].info |= cpu_to_le32(QTN_BD_EMPTY);
210
211 pr_debug("TX descriptor table: vaddr=0x%p paddr=%pad\n", vaddr, &paddr);
212
213 priv->tx_bd_r_index = 0;
214 priv->tx_bd_w_index = 0;
215
216 /* rx bd */
217
218 vaddr = ((struct qtnf_topaz_tx_bd *)vaddr) + priv->tx_bd_num;
219 paddr += priv->tx_bd_num * sizeof(struct qtnf_topaz_tx_bd);
220
221 ts->rx_bd_vbase = vaddr;
222 qtnf_non_posted_write(paddr, &bda->bda_rc_rx_bd_base);
223
224 pr_debug("RX descriptor table: vaddr=0x%p paddr=%pad\n", vaddr, &paddr);
225
226 /* extra shared params */
227
228 vaddr = ((struct qtnf_topaz_rx_bd *)vaddr) + priv->rx_bd_num;
229 paddr += priv->rx_bd_num * sizeof(struct qtnf_topaz_rx_bd);
230
231 extra_params = (struct qtnf_extra_bd_params __iomem *)vaddr;
232
233 ts->ep_next_rx_pkt = &extra_params->param1;
234 qtnf_non_posted_write(paddr + QTNF_BD_PARAM_OFFSET(1),
235 &bda->bda_ep_next_pkt);
236 ts->txqueue_wake = &extra_params->param2;
237 ts->ep_pmstate = &extra_params->param3;
238 ts->dma_msi_dummy = paddr + QTNF_BD_PARAM_OFFSET(4);
239
240 return 0;
241 }
242
243 static int
244 topaz_skb2rbd_attach(struct qtnf_pcie_topaz_state *ts, u16 index, u32 wrap)
245 {
246 struct qtnf_topaz_rx_bd *rxbd = &ts->rx_bd_vbase[index];
247 struct sk_buff *skb;
248 dma_addr_t paddr;
249
250 skb = netdev_alloc_skb_ip_align(NULL, SKB_BUF_SIZE);
251 if (!skb) {
252 ts->base.rx_skb[index] = NULL;
253 return -ENOMEM;
254 }
255
256 ts->base.rx_skb[index] = skb;
257
258 paddr = pci_map_single(ts->base.pdev, skb->data,
259 SKB_BUF_SIZE, PCI_DMA_FROMDEVICE);
260 if (pci_dma_mapping_error(ts->base.pdev, paddr)) {
261 pr_err("skb mapping error: %pad\n", &paddr);
262 return -ENOMEM;
263 }
264
265 rxbd->addr = cpu_to_le32(QTN_HOST_LO32(paddr));
266 rxbd->info = cpu_to_le32(QTN_BD_EMPTY | wrap);
267
268 ts->base.rx_bd_w_index = index;
269
270 return 0;
271 }
272
273 static int topaz_alloc_rx_buffers(struct qtnf_pcie_topaz_state *ts)
274 {
275 u16 i;
276 int ret = 0;
277
278 memset(ts->rx_bd_vbase, 0x0,
279 ts->base.rx_bd_num * sizeof(struct qtnf_topaz_rx_bd));
280
281 for (i = 0; i < ts->base.rx_bd_num; i++) {
282 ret = topaz_skb2rbd_attach(ts, i, 0);
283 if (ret)
284 break;
285 }
286
287 ts->rx_bd_vbase[ts->base.rx_bd_num - 1].info |=
288 cpu_to_le32(QTN_BD_WRAP);
289
290 return ret;
291 }
292
293 /* all rx/tx activity should have ceased before calling this function */
294 static void qtnf_topaz_free_xfer_buffers(struct qtnf_pcie_topaz_state *ts)
295 {
296 struct qtnf_pcie_bus_priv *priv = &ts->base;
297 struct qtnf_topaz_rx_bd *rxbd;
298 struct qtnf_topaz_tx_bd *txbd;
299 struct sk_buff *skb;
300 dma_addr_t paddr;
301 int i;
302
303 /* free rx buffers */
304 for (i = 0; i < priv->rx_bd_num; i++) {
305 if (priv->rx_skb && priv->rx_skb[i]) {
306 rxbd = &ts->rx_bd_vbase[i];
307 skb = priv->rx_skb[i];
308 paddr = QTN_HOST_ADDR(0x0, le32_to_cpu(rxbd->addr));
309 pci_unmap_single(priv->pdev, paddr, SKB_BUF_SIZE,
310 PCI_DMA_FROMDEVICE);
311 dev_kfree_skb_any(skb);
312 priv->rx_skb[i] = NULL;
313 rxbd->addr = 0;
314 rxbd->info = 0;
315 }
316 }
317
318 /* free tx buffers */
319 for (i = 0; i < priv->tx_bd_num; i++) {
320 if (priv->tx_skb && priv->tx_skb[i]) {
321 txbd = &ts->tx_bd_vbase[i];
322 skb = priv->tx_skb[i];
323 paddr = QTN_HOST_ADDR(0x0, le32_to_cpu(txbd->addr));
324 pci_unmap_single(priv->pdev, paddr, SKB_BUF_SIZE,
325 PCI_DMA_TODEVICE);
326 dev_kfree_skb_any(skb);
327 priv->tx_skb[i] = NULL;
328 txbd->addr = 0;
329 txbd->info = 0;
330 }
331 }
332 }
333
334 static int qtnf_pcie_topaz_init_xfer(struct qtnf_pcie_topaz_state *ts,
335 unsigned int tx_bd_size,
336 unsigned int rx_bd_size)
337 {
338 struct qtnf_topaz_bda __iomem *bda = ts->bda;
339 struct qtnf_pcie_bus_priv *priv = &ts->base;
340 int ret;
341
342 if (tx_bd_size == 0)
343 tx_bd_size = TOPAZ_TX_BD_SIZE_DEFAULT;
344
345 /* check TX BD queue max length according to struct qtnf_topaz_bda */
346 if (tx_bd_size > QTN_PCIE_RC_TX_QUEUE_LEN) {
347 pr_warn("TX BD queue cannot exceed %d\n",
348 QTN_PCIE_RC_TX_QUEUE_LEN);
349 tx_bd_size = QTN_PCIE_RC_TX_QUEUE_LEN;
350 }
351
352 priv->tx_bd_num = tx_bd_size;
353 qtnf_non_posted_write(priv->tx_bd_num, &bda->bda_rc_tx_bd_num);
354
355 if (rx_bd_size == 0)
356 rx_bd_size = TOPAZ_RX_BD_SIZE_DEFAULT;
357
358 if (rx_bd_size > TOPAZ_RX_BD_SIZE_DEFAULT) {
359 pr_warn("RX BD queue cannot exceed %d\n",
360 TOPAZ_RX_BD_SIZE_DEFAULT);
361 rx_bd_size = TOPAZ_RX_BD_SIZE_DEFAULT;
362 }
363
364 priv->rx_bd_num = rx_bd_size;
365 qtnf_non_posted_write(priv->rx_bd_num, &bda->bda_rc_rx_bd_num);
366
367 priv->rx_bd_w_index = 0;
368 priv->rx_bd_r_index = 0;
369
370 ret = qtnf_pcie_alloc_skb_array(priv);
371 if (ret) {
372 pr_err("failed to allocate skb array\n");
373 return ret;
374 }
375
376 ret = topaz_alloc_bd_table(ts, bda);
377 if (ret) {
378 pr_err("failed to allocate bd table\n");
379 return ret;
380 }
381
382 ret = topaz_alloc_rx_buffers(ts);
383 if (ret) {
384 pr_err("failed to allocate rx buffers\n");
385 return ret;
386 }
387
388 return ret;
389 }
390
391 static void qtnf_topaz_data_tx_reclaim(struct qtnf_pcie_topaz_state *ts)
392 {
393 struct qtnf_pcie_bus_priv *priv = &ts->base;
394 struct qtnf_topaz_tx_bd *txbd;
395 struct sk_buff *skb;
396 unsigned long flags;
397 dma_addr_t paddr;
398 u32 tx_done_index;
399 int count = 0;
400 int i;
401
402 spin_lock_irqsave(&priv->tx_reclaim_lock, flags);
403
404 tx_done_index = readl(ts->ep_next_rx_pkt);
405 i = priv->tx_bd_r_index;
406
407 if (CIRC_CNT(priv->tx_bd_w_index, tx_done_index, priv->tx_bd_num))
408 writel(TOPAZ_IPC_IRQ_WORD(TOPAZ_RC_TX_DONE_IRQ),
409 TOPAZ_LH_IPC4_INT(priv->sysctl_bar));
410
411 while (CIRC_CNT(tx_done_index, i, priv->tx_bd_num)) {
412 skb = priv->tx_skb[i];
413
414 if (likely(skb)) {
415 txbd = &ts->tx_bd_vbase[i];
416 paddr = QTN_HOST_ADDR(0x0, le32_to_cpu(txbd->addr));
417 pci_unmap_single(priv->pdev, paddr, skb->len,
418 PCI_DMA_TODEVICE);
419
420 if (skb->dev) {
421 dev_sw_netstats_tx_add(skb->dev, 1, skb->len);
422 if (unlikely(priv->tx_stopped)) {
423 qtnf_wake_all_queues(skb->dev);
424 priv->tx_stopped = 0;
425 }
426 }
427
428 dev_kfree_skb_any(skb);
429 }
430
431 priv->tx_skb[i] = NULL;
432 count++;
433
434 if (++i >= priv->tx_bd_num)
435 i = 0;
436 }
437
438 priv->tx_reclaim_done += count;
439 priv->tx_reclaim_req++;
440 priv->tx_bd_r_index = i;
441
442 spin_unlock_irqrestore(&priv->tx_reclaim_lock, flags);
443 }
444
445 static void qtnf_try_stop_xmit(struct qtnf_bus *bus, struct net_device *ndev)
446 {
447 struct qtnf_pcie_topaz_state *ts = (void *)get_bus_priv(bus);
448
449 if (ndev) {
450 netif_tx_stop_all_queues(ndev);
451 ts->base.tx_stopped = 1;
452 }
453
454 writel(0x0, ts->txqueue_wake);
455
456 /* sync up tx queue status before generating interrupt */
457 dma_wmb();
458
459 /* send irq to card: tx stopped */
460 writel(TOPAZ_IPC_IRQ_WORD(TOPAZ_RC_TX_STOP_IRQ),
461 TOPAZ_LH_IPC4_INT(ts->base.sysctl_bar));
462
463 /* schedule reclaim attempt */
464 tasklet_hi_schedule(&ts->base.reclaim_tq);
465 }
466
467 static void qtnf_try_wake_xmit(struct qtnf_bus *bus, struct net_device *ndev)
468 {
469 struct qtnf_pcie_topaz_state *ts = get_bus_priv(bus);
470 int ready;
471
472 ready = readl(ts->txqueue_wake);
473 if (ready) {
474 netif_wake_queue(ndev);
475 } else {
476 /* re-send irq to card: tx stopped */
477 writel(TOPAZ_IPC_IRQ_WORD(TOPAZ_RC_TX_STOP_IRQ),
478 TOPAZ_LH_IPC4_INT(ts->base.sysctl_bar));
479 }
480 }
481
482 static int qtnf_tx_queue_ready(struct qtnf_pcie_topaz_state *ts)
483 {
484 struct qtnf_pcie_bus_priv *priv = &ts->base;
485
486 if (!CIRC_SPACE(priv->tx_bd_w_index, priv->tx_bd_r_index,
487 priv->tx_bd_num)) {
488 qtnf_topaz_data_tx_reclaim(ts);
489
490 if (!CIRC_SPACE(priv->tx_bd_w_index, priv->tx_bd_r_index,
491 priv->tx_bd_num)) {
492 priv->tx_full_count++;
493 return 0;
494 }
495 }
496
497 return 1;
498 }
499
500 static int qtnf_pcie_data_tx(struct qtnf_bus *bus, struct sk_buff *skb,
501 unsigned int macid, unsigned int vifid)
502 {
503 struct qtnf_pcie_topaz_state *ts = (void *)get_bus_priv(bus);
504 struct qtnf_pcie_bus_priv *priv = &ts->base;
505 struct qtnf_topaz_bda __iomem *bda = ts->bda;
506 struct qtnf_topaz_tx_bd *txbd;
507 dma_addr_t skb_paddr;
508 unsigned long flags;
509 int ret = 0;
510 int len;
511 int i;
512
513 spin_lock_irqsave(&priv->tx_lock, flags);
514
515 if (!qtnf_tx_queue_ready(ts)) {
516 qtnf_try_stop_xmit(bus, skb->dev);
517 spin_unlock_irqrestore(&priv->tx_lock, flags);
518 return NETDEV_TX_BUSY;
519 }
520
521 i = priv->tx_bd_w_index;
522 priv->tx_skb[i] = skb;
523 len = skb->len;
524
525 skb_paddr = pci_map_single(priv->pdev, skb->data,
526 skb->len, PCI_DMA_TODEVICE);
527 if (pci_dma_mapping_error(priv->pdev, skb_paddr)) {
528 ret = -ENOMEM;
529 goto tx_done;
530 }
531
532 txbd = &ts->tx_bd_vbase[i];
533 txbd->addr = cpu_to_le32(QTN_HOST_LO32(skb_paddr));
534
535 writel(QTN_HOST_LO32(skb_paddr), &bda->request[i].addr);
536 writel(len | QTN_PCIE_TX_VALID_PKT, &bda->request[i].info);
537
538 /* sync up descriptor updates before generating interrupt */
539 dma_wmb();
540
541 /* generate irq to card: tx done */
542 writel(TOPAZ_IPC_IRQ_WORD(TOPAZ_RC_TX_DONE_IRQ),
543 TOPAZ_LH_IPC4_INT(priv->sysctl_bar));
544
545 if (++i >= priv->tx_bd_num)
546 i = 0;
547
548 priv->tx_bd_w_index = i;
549
550 tx_done:
551 if (ret) {
552 if (skb->dev)
553 skb->dev->stats.tx_dropped++;
554 dev_kfree_skb_any(skb);
555 }
556
557 priv->tx_done_count++;
558 spin_unlock_irqrestore(&priv->tx_lock, flags);
559
560 qtnf_topaz_data_tx_reclaim(ts);
561
562 return NETDEV_TX_OK;
563 }
564
565 static irqreturn_t qtnf_pcie_topaz_interrupt(int irq, void *data)
566 {
567 struct qtnf_bus *bus = (struct qtnf_bus *)data;
568 struct qtnf_pcie_topaz_state *ts = (void *)get_bus_priv(bus);
569 struct qtnf_pcie_bus_priv *priv = &ts->base;
570
571 if (!priv->msi_enabled && !qtnf_topaz_intx_asserted(ts))
572 return IRQ_NONE;
573
574 if (!priv->msi_enabled)
575 qtnf_deassert_intx(ts);
576
577 priv->pcie_irq_count++;
578
579 qtnf_shm_ipc_irq_handler(&priv->shm_ipc_ep_in);
580 qtnf_shm_ipc_irq_handler(&priv->shm_ipc_ep_out);
581
582 if (napi_schedule_prep(&bus->mux_napi)) {
583 disable_rx_irqs(ts);
584 __napi_schedule(&bus->mux_napi);
585 }
586
587 tasklet_hi_schedule(&priv->reclaim_tq);
588
589 return IRQ_HANDLED;
590 }
591
592 static int qtnf_rx_data_ready(struct qtnf_pcie_topaz_state *ts)
593 {
594 u16 index = ts->base.rx_bd_r_index;
595 struct qtnf_topaz_rx_bd *rxbd;
596 u32 descw;
597
598 rxbd = &ts->rx_bd_vbase[index];
599 descw = le32_to_cpu(rxbd->info);
600
601 if (descw & QTN_BD_EMPTY)
602 return 0;
603
604 return 1;
605 }
606
607 static int qtnf_topaz_rx_poll(struct napi_struct *napi, int budget)
608 {
609 struct qtnf_bus *bus = container_of(napi, struct qtnf_bus, mux_napi);
610 struct qtnf_pcie_topaz_state *ts = (void *)get_bus_priv(bus);
611 struct qtnf_pcie_bus_priv *priv = &ts->base;
612 struct net_device *ndev = NULL;
613 struct sk_buff *skb = NULL;
614 int processed = 0;
615 struct qtnf_topaz_rx_bd *rxbd;
616 dma_addr_t skb_paddr;
617 int consume;
618 u32 descw;
619 u32 poffset;
620 u32 psize;
621 u16 r_idx;
622 u16 w_idx;
623 int ret;
624
625 while (processed < budget) {
626 if (!qtnf_rx_data_ready(ts))
627 goto rx_out;
628
629 r_idx = priv->rx_bd_r_index;
630 rxbd = &ts->rx_bd_vbase[r_idx];
631 descw = le32_to_cpu(rxbd->info);
632
633 skb = priv->rx_skb[r_idx];
634 poffset = QTN_GET_OFFSET(descw);
635 psize = QTN_GET_LEN(descw);
636 consume = 1;
637
638 if (descw & QTN_BD_EMPTY) {
639 pr_warn("skip invalid rxbd[%d]\n", r_idx);
640 consume = 0;
641 }
642
643 if (!skb) {
644 pr_warn("skip missing rx_skb[%d]\n", r_idx);
645 consume = 0;
646 }
647
648 if (skb && (skb_tailroom(skb) < psize)) {
649 pr_err("skip packet with invalid length: %u > %u\n",
650 psize, skb_tailroom(skb));
651 consume = 0;
652 }
653
654 if (skb) {
655 skb_paddr = QTN_HOST_ADDR(0x0, le32_to_cpu(rxbd->addr));
656 pci_unmap_single(priv->pdev, skb_paddr, SKB_BUF_SIZE,
657 PCI_DMA_FROMDEVICE);
658 }
659
660 if (consume) {
661 skb_reserve(skb, poffset);
662 skb_put(skb, psize);
663 ndev = qtnf_classify_skb(bus, skb);
664 if (likely(ndev)) {
665 dev_sw_netstats_rx_add(ndev, skb->len);
666 skb->protocol = eth_type_trans(skb, ndev);
667 netif_receive_skb(skb);
668 } else {
669 pr_debug("drop untagged skb\n");
670 bus->mux_dev.stats.rx_dropped++;
671 dev_kfree_skb_any(skb);
672 }
673 } else {
674 if (skb) {
675 bus->mux_dev.stats.rx_dropped++;
676 dev_kfree_skb_any(skb);
677 }
678 }
679
680 /* notify card about recv packets once per several packets */
681 if (((++ts->rx_pkt_count) & RX_DONE_INTR_MSK) == 0)
682 writel(TOPAZ_IPC_IRQ_WORD(TOPAZ_RC_RX_DONE_IRQ),
683 TOPAZ_LH_IPC4_INT(priv->sysctl_bar));
684
685 priv->rx_skb[r_idx] = NULL;
686 if (++r_idx >= priv->rx_bd_num)
687 r_idx = 0;
688
689 priv->rx_bd_r_index = r_idx;
690
691 /* repalce processed buffer by a new one */
692 w_idx = priv->rx_bd_w_index;
693 while (CIRC_SPACE(priv->rx_bd_w_index, priv->rx_bd_r_index,
694 priv->rx_bd_num) > 0) {
695 if (++w_idx >= priv->rx_bd_num)
696 w_idx = 0;
697
698 ret = topaz_skb2rbd_attach(ts, w_idx,
699 descw & QTN_BD_WRAP);
700 if (ret) {
701 pr_err("failed to allocate new rx_skb[%d]\n",
702 w_idx);
703 break;
704 }
705 }
706
707 processed++;
708 }
709
710 rx_out:
711 if (processed < budget) {
712 napi_complete(napi);
713 enable_rx_irqs(ts);
714 }
715
716 return processed;
717 }
718
719 static void
720 qtnf_pcie_data_tx_timeout(struct qtnf_bus *bus, struct net_device *ndev)
721 {
722 struct qtnf_pcie_topaz_state *ts = get_bus_priv(bus);
723
724 qtnf_try_wake_xmit(bus, ndev);
725 tasklet_hi_schedule(&ts->base.reclaim_tq);
726 }
727
728 static void qtnf_pcie_data_rx_start(struct qtnf_bus *bus)
729 {
730 struct qtnf_pcie_topaz_state *ts = get_bus_priv(bus);
731
732 napi_enable(&bus->mux_napi);
733 enable_rx_irqs(ts);
734 }
735
736 static void qtnf_pcie_data_rx_stop(struct qtnf_bus *bus)
737 {
738 struct qtnf_pcie_topaz_state *ts = get_bus_priv(bus);
739
740 disable_rx_irqs(ts);
741 napi_disable(&bus->mux_napi);
742 }
743
744 static struct qtnf_bus_ops qtnf_pcie_topaz_bus_ops = {
745 /* control path methods */
746 .control_tx = qtnf_pcie_control_tx,
747
748 /* data path methods */
749 .data_tx = qtnf_pcie_data_tx,
750 .data_tx_timeout = qtnf_pcie_data_tx_timeout,
751 .data_rx_start = qtnf_pcie_data_rx_start,
752 .data_rx_stop = qtnf_pcie_data_rx_stop,
753 };
754
755 static int qtnf_dbg_irq_stats(struct seq_file *s, void *data)
756 {
757 struct qtnf_bus *bus = dev_get_drvdata(s->private);
758 struct qtnf_pcie_topaz_state *ts = get_bus_priv(bus);
759
760 seq_printf(s, "pcie_irq_count(%u)\n", ts->base.pcie_irq_count);
761
762 return 0;
763 }
764
765 static int qtnf_dbg_pkt_stats(struct seq_file *s, void *data)
766 {
767 struct qtnf_bus *bus = dev_get_drvdata(s->private);
768 struct qtnf_pcie_topaz_state *ts = get_bus_priv(bus);
769 struct qtnf_pcie_bus_priv *priv = &ts->base;
770 u32 tx_done_index = readl(ts->ep_next_rx_pkt);
771
772 seq_printf(s, "tx_full_count(%u)\n", priv->tx_full_count);
773 seq_printf(s, "tx_done_count(%u)\n", priv->tx_done_count);
774 seq_printf(s, "tx_reclaim_done(%u)\n", priv->tx_reclaim_done);
775 seq_printf(s, "tx_reclaim_req(%u)\n", priv->tx_reclaim_req);
776
777 seq_printf(s, "tx_bd_r_index(%u)\n", priv->tx_bd_r_index);
778 seq_printf(s, "tx_done_index(%u)\n", tx_done_index);
779 seq_printf(s, "tx_bd_w_index(%u)\n", priv->tx_bd_w_index);
780
781 seq_printf(s, "tx host queue len(%u)\n",
782 CIRC_CNT(priv->tx_bd_w_index, priv->tx_bd_r_index,
783 priv->tx_bd_num));
784 seq_printf(s, "tx reclaim queue len(%u)\n",
785 CIRC_CNT(tx_done_index, priv->tx_bd_r_index,
786 priv->tx_bd_num));
787 seq_printf(s, "tx card queue len(%u)\n",
788 CIRC_CNT(priv->tx_bd_w_index, tx_done_index,
789 priv->tx_bd_num));
790
791 seq_printf(s, "rx_bd_r_index(%u)\n", priv->rx_bd_r_index);
792 seq_printf(s, "rx_bd_w_index(%u)\n", priv->rx_bd_w_index);
793 seq_printf(s, "rx alloc queue len(%u)\n",
794 CIRC_SPACE(priv->rx_bd_w_index, priv->rx_bd_r_index,
795 priv->rx_bd_num));
796
797 return 0;
798 }
799
800 static void qtnf_reset_dma_offset(struct qtnf_pcie_topaz_state *ts)
801 {
802 struct qtnf_topaz_bda __iomem *bda = ts->bda;
803 u32 offset = readl(&bda->bda_dma_offset);
804
805 if ((offset & PCIE_DMA_OFFSET_ERROR_MASK) != PCIE_DMA_OFFSET_ERROR)
806 return;
807
808 writel(0x0, &bda->bda_dma_offset);
809 }
810
811 static int qtnf_pcie_endian_detect(struct qtnf_pcie_topaz_state *ts)
812 {
813 struct qtnf_topaz_bda __iomem *bda = ts->bda;
814 u32 timeout = 0;
815 u32 endian;
816 int ret = 0;
817
818 writel(QTN_PCI_ENDIAN_DETECT_DATA, &bda->bda_pci_endian);
819
820 /* flush endian modifications before status update */
821 dma_wmb();
822
823 writel(QTN_PCI_ENDIAN_VALID_STATUS, &bda->bda_pci_pre_status);
824
825 while (readl(&bda->bda_pci_post_status) !=
826 QTN_PCI_ENDIAN_VALID_STATUS) {
827 usleep_range(1000, 1200);
828 if (++timeout > QTN_FW_DL_TIMEOUT_MS) {
829 pr_err("card endianness detection timed out\n");
830 ret = -ETIMEDOUT;
831 goto endian_out;
832 }
833 }
834
835 /* do not read before status is updated */
836 dma_rmb();
837
838 endian = readl(&bda->bda_pci_endian);
839 WARN(endian != QTN_PCI_LITTLE_ENDIAN,
840 "%s: unexpected card endianness", __func__);
841
842 endian_out:
843 writel(0, &bda->bda_pci_pre_status);
844 writel(0, &bda->bda_pci_post_status);
845 writel(0, &bda->bda_pci_endian);
846
847 return ret;
848 }
849
850 static int qtnf_pre_init_ep(struct qtnf_bus *bus)
851 {
852 struct qtnf_pcie_topaz_state *ts = (void *)get_bus_priv(bus);
853 struct qtnf_topaz_bda __iomem *bda = ts->bda;
854 u32 flags;
855 int ret;
856
857 ret = qtnf_pcie_endian_detect(ts);
858 if (ret < 0) {
859 pr_err("failed to detect card endianness\n");
860 return ret;
861 }
862
863 writeb(ts->base.msi_enabled, &ts->bda->bda_rc_msi_enabled);
864 qtnf_reset_dma_offset(ts);
865
866 /* notify card about driver type and boot mode */
867 flags = readl(&bda->bda_flags) | QTN_BDA_HOST_QLINK_DRV;
868
869 if (ts->base.flashboot)
870 flags |= QTN_BDA_FLASH_BOOT;
871 else
872 flags &= ~QTN_BDA_FLASH_BOOT;
873
874 writel(flags, &bda->bda_flags);
875
876 qtnf_set_state(&ts->bda->bda_bootstate, QTN_BDA_FW_HOST_RDY);
877 if (qtnf_poll_state(&ts->bda->bda_bootstate, QTN_BDA_FW_TARGET_RDY,
878 QTN_FW_DL_TIMEOUT_MS)) {
879 pr_err("card is not ready to boot...\n");
880 return -ETIMEDOUT;
881 }
882
883 return ret;
884 }
885
886 static int qtnf_post_init_ep(struct qtnf_pcie_topaz_state *ts)
887 {
888 struct pci_dev *pdev = ts->base.pdev;
889
890 setup_rx_irqs(ts);
891 disable_rx_irqs(ts);
892
893 if (qtnf_poll_state(&ts->bda->bda_bootstate, QTN_BDA_FW_QLINK_DONE,
894 QTN_FW_QLINK_TIMEOUT_MS))
895 return -ETIMEDOUT;
896
897 enable_irq(pdev->irq);
898 return 0;
899 }
900
901 static int
902 qtnf_ep_fw_load(struct qtnf_pcie_topaz_state *ts, const u8 *fw, u32 fw_size)
903 {
904 struct qtnf_topaz_bda __iomem *bda = ts->bda;
905 struct pci_dev *pdev = ts->base.pdev;
906 u32 remaining = fw_size;
907 u8 *curr = (u8 *)fw;
908 u32 blksize;
909 u32 nblocks;
910 u32 offset;
911 u32 count;
912 u32 size;
913 dma_addr_t paddr;
914 void *data;
915 int ret = 0;
916
917 pr_debug("FW upload started: fw_addr = 0x%p, size=%d\n", fw, fw_size);
918
919 blksize = ts->base.fw_blksize;
920
921 if (blksize < PAGE_SIZE)
922 blksize = PAGE_SIZE;
923
924 while (blksize >= PAGE_SIZE) {
925 pr_debug("allocating %u bytes to upload FW\n", blksize);
926 data = dma_alloc_coherent(&pdev->dev, blksize,
927 &paddr, GFP_KERNEL);
928 if (data)
929 break;
930 blksize /= 2;
931 }
932
933 if (!data) {
934 pr_err("failed to allocate DMA buffer for FW upload\n");
935 ret = -ENOMEM;
936 goto fw_load_out;
937 }
938
939 nblocks = NBLOCKS(fw_size, blksize);
940 offset = readl(&bda->bda_dma_offset);
941
942 qtnf_set_state(&ts->bda->bda_bootstate, QTN_BDA_FW_HOST_LOAD);
943 if (qtnf_poll_state(&ts->bda->bda_bootstate, QTN_BDA_FW_EP_RDY,
944 QTN_FW_DL_TIMEOUT_MS)) {
945 pr_err("card is not ready to download FW\n");
946 ret = -ETIMEDOUT;
947 goto fw_load_map;
948 }
949
950 for (count = 0 ; count < nblocks; count++) {
951 size = (remaining > blksize) ? blksize : remaining;
952
953 memcpy(data, curr, size);
954 qtnf_non_posted_write(paddr + offset, &bda->bda_img);
955 qtnf_non_posted_write(size, &bda->bda_img_size);
956
957 pr_debug("chunk[%u] VA[0x%p] PA[%pad] sz[%u]\n",
958 count, (void *)curr, &paddr, size);
959
960 qtnf_set_state(&ts->bda->bda_bootstate, QTN_BDA_FW_BLOCK_RDY);
961 if (qtnf_poll_state(&ts->bda->bda_bootstate,
962 QTN_BDA_FW_BLOCK_DONE,
963 QTN_FW_DL_TIMEOUT_MS)) {
964 pr_err("confirmation for block #%d timed out\n", count);
965 ret = -ETIMEDOUT;
966 goto fw_load_map;
967 }
968
969 remaining = (remaining < size) ? remaining : (remaining - size);
970 curr += size;
971 }
972
973 /* upload completion mark: zero-sized block */
974 qtnf_non_posted_write(0, &bda->bda_img);
975 qtnf_non_posted_write(0, &bda->bda_img_size);
976
977 qtnf_set_state(&ts->bda->bda_bootstate, QTN_BDA_FW_BLOCK_RDY);
978 if (qtnf_poll_state(&ts->bda->bda_bootstate, QTN_BDA_FW_BLOCK_DONE,
979 QTN_FW_DL_TIMEOUT_MS)) {
980 pr_err("confirmation for the last block timed out\n");
981 ret = -ETIMEDOUT;
982 goto fw_load_map;
983 }
984
985 /* RC is done */
986 qtnf_set_state(&ts->bda->bda_bootstate, QTN_BDA_FW_BLOCK_END);
987 if (qtnf_poll_state(&ts->bda->bda_bootstate, QTN_BDA_FW_LOAD_DONE,
988 QTN_FW_DL_TIMEOUT_MS)) {
989 pr_err("confirmation for FW upload completion timed out\n");
990 ret = -ETIMEDOUT;
991 goto fw_load_map;
992 }
993
994 pr_debug("FW upload completed: totally sent %d blocks\n", count);
995
996 fw_load_map:
997 dma_free_coherent(&pdev->dev, blksize, data, paddr);
998
999 fw_load_out:
1000 return ret;
1001 }
1002
1003 static int qtnf_topaz_fw_upload(struct qtnf_pcie_topaz_state *ts,
1004 const char *fwname)
1005 {
1006 const struct firmware *fw;
1007 struct pci_dev *pdev = ts->base.pdev;
1008 int ret;
1009
1010 if (qtnf_poll_state(&ts->bda->bda_bootstate,
1011 QTN_BDA_FW_LOAD_RDY,
1012 QTN_FW_DL_TIMEOUT_MS)) {
1013 pr_err("%s: card is not ready\n", fwname);
1014 return -1;
1015 }
1016
1017 pr_info("starting firmware upload: %s\n", fwname);
1018
1019 ret = request_firmware(&fw, fwname, &pdev->dev);
1020 if (ret < 0) {
1021 pr_err("%s: request_firmware error %d\n", fwname, ret);
1022 return -1;
1023 }
1024
1025 ret = qtnf_ep_fw_load(ts, fw->data, fw->size);
1026 release_firmware(fw);
1027
1028 if (ret)
1029 pr_err("%s: FW upload error\n", fwname);
1030
1031 return ret;
1032 }
1033
1034 static void qtnf_topaz_fw_work_handler(struct work_struct *work)
1035 {
1036 struct qtnf_bus *bus = container_of(work, struct qtnf_bus, fw_work);
1037 struct qtnf_pcie_topaz_state *ts = (void *)get_bus_priv(bus);
1038 int bootloader_needed = readl(&ts->bda->bda_flags) & QTN_BDA_XMIT_UBOOT;
1039 struct pci_dev *pdev = ts->base.pdev;
1040 int ret;
1041
1042 qtnf_set_state(&ts->bda->bda_bootstate, QTN_BDA_FW_TARGET_BOOT);
1043
1044 if (bootloader_needed) {
1045 ret = qtnf_topaz_fw_upload(ts, QTN_PCI_TOPAZ_BOOTLD_NAME);
1046 if (ret)
1047 goto fw_load_exit;
1048
1049 ret = qtnf_pre_init_ep(bus);
1050 if (ret)
1051 goto fw_load_exit;
1052
1053 qtnf_set_state(&ts->bda->bda_bootstate,
1054 QTN_BDA_FW_TARGET_BOOT);
1055 }
1056
1057 if (ts->base.flashboot) {
1058 pr_info("booting firmware from flash\n");
1059
1060 ret = qtnf_poll_state(&ts->bda->bda_bootstate,
1061 QTN_BDA_FW_FLASH_BOOT,
1062 QTN_FW_DL_TIMEOUT_MS);
1063 if (ret)
1064 goto fw_load_exit;
1065 } else {
1066 ret = qtnf_topaz_fw_upload(ts, QTN_PCI_TOPAZ_FW_NAME);
1067 if (ret)
1068 goto fw_load_exit;
1069
1070 qtnf_set_state(&ts->bda->bda_bootstate, QTN_BDA_FW_START);
1071 ret = qtnf_poll_state(&ts->bda->bda_bootstate,
1072 QTN_BDA_FW_CONFIG,
1073 QTN_FW_QLINK_TIMEOUT_MS);
1074 if (ret) {
1075 pr_err("FW bringup timed out\n");
1076 goto fw_load_exit;
1077 }
1078
1079 qtnf_set_state(&ts->bda->bda_bootstate, QTN_BDA_FW_RUN);
1080 ret = qtnf_poll_state(&ts->bda->bda_bootstate,
1081 QTN_BDA_FW_RUNNING,
1082 QTN_FW_QLINK_TIMEOUT_MS);
1083 if (ret) {
1084 pr_err("card bringup timed out\n");
1085 goto fw_load_exit;
1086 }
1087 }
1088
1089 ret = qtnf_post_init_ep(ts);
1090 if (ret) {
1091 pr_err("FW runtime failure\n");
1092 goto fw_load_exit;
1093 }
1094
1095 pr_info("firmware is up and running\n");
1096
1097 ret = qtnf_pcie_fw_boot_done(bus);
1098 if (ret)
1099 goto fw_load_exit;
1100
1101 qtnf_debugfs_add_entry(bus, "pkt_stats", qtnf_dbg_pkt_stats);
1102 qtnf_debugfs_add_entry(bus, "irq_stats", qtnf_dbg_irq_stats);
1103
1104 fw_load_exit:
1105 put_device(&pdev->dev);
1106 }
1107
1108 static void qtnf_reclaim_tasklet_fn(struct tasklet_struct *t)
1109 {
1110 struct qtnf_pcie_topaz_state *ts = from_tasklet(ts, t, base.reclaim_tq);
1111
1112 qtnf_topaz_data_tx_reclaim(ts);
1113 }
1114
1115 static u64 qtnf_topaz_dma_mask_get(void)
1116 {
1117 return DMA_BIT_MASK(32);
1118 }
1119
1120 static int qtnf_pcie_topaz_probe(struct qtnf_bus *bus,
1121 unsigned int tx_bd_num, unsigned int rx_bd_num)
1122 {
1123 struct qtnf_pcie_topaz_state *ts = get_bus_priv(bus);
1124 struct pci_dev *pdev = ts->base.pdev;
1125 struct qtnf_shm_ipc_int ipc_int;
1126 unsigned long irqflags;
1127 int ret;
1128
1129 bus->bus_ops = &qtnf_pcie_topaz_bus_ops;
1130 INIT_WORK(&bus->fw_work, qtnf_topaz_fw_work_handler);
1131 ts->bda = ts->base.epmem_bar;
1132
1133 /* assign host msi irq before card init */
1134 if (ts->base.msi_enabled)
1135 irqflags = IRQF_NOBALANCING;
1136 else
1137 irqflags = IRQF_NOBALANCING | IRQF_SHARED;
1138
1139 ret = devm_request_irq(&pdev->dev, pdev->irq,
1140 &qtnf_pcie_topaz_interrupt,
1141 irqflags, "qtnf_topaz_irq", (void *)bus);
1142 if (ret) {
1143 pr_err("failed to request pcie irq %d\n", pdev->irq);
1144 return ret;
1145 }
1146
1147 disable_irq(pdev->irq);
1148
1149 ret = qtnf_pre_init_ep(bus);
1150 if (ret) {
1151 pr_err("failed to init card\n");
1152 return ret;
1153 }
1154
1155 ret = qtnf_pcie_topaz_init_xfer(ts, tx_bd_num, rx_bd_num);
1156 if (ret) {
1157 pr_err("PCIE xfer init failed\n");
1158 return ret;
1159 }
1160
1161 tasklet_setup(&ts->base.reclaim_tq, qtnf_reclaim_tasklet_fn);
1162 netif_napi_add(&bus->mux_dev, &bus->mux_napi,
1163 qtnf_topaz_rx_poll, 10);
1164
1165 ipc_int.fn = qtnf_topaz_ipc_gen_ep_int;
1166 ipc_int.arg = ts;
1167 qtnf_pcie_init_shm_ipc(&ts->base, &ts->bda->bda_shm_reg1,
1168 &ts->bda->bda_shm_reg2, &ipc_int);
1169
1170 return 0;
1171 }
1172
1173 static void qtnf_pcie_topaz_remove(struct qtnf_bus *bus)
1174 {
1175 struct qtnf_pcie_topaz_state *ts = get_bus_priv(bus);
1176
1177 qtnf_topaz_reset_ep(ts);
1178 qtnf_topaz_free_xfer_buffers(ts);
1179 }
1180
1181 #ifdef CONFIG_PM_SLEEP
1182 static int qtnf_pcie_topaz_suspend(struct qtnf_bus *bus)
1183 {
1184 struct qtnf_pcie_topaz_state *ts = get_bus_priv(bus);
1185 struct pci_dev *pdev = ts->base.pdev;
1186
1187 writel((u32 __force)PCI_D3hot, ts->ep_pmstate);
1188 dma_wmb();
1189 writel(TOPAZ_IPC_IRQ_WORD(TOPAZ_RC_PM_EP_IRQ),
1190 TOPAZ_LH_IPC4_INT(ts->base.sysctl_bar));
1191
1192 pci_save_state(pdev);
1193 pci_enable_wake(pdev, PCI_D3hot, 1);
1194 pci_set_power_state(pdev, PCI_D3hot);
1195
1196 return 0;
1197 }
1198
1199 static int qtnf_pcie_topaz_resume(struct qtnf_bus *bus)
1200 {
1201 struct qtnf_pcie_topaz_state *ts = get_bus_priv(bus);
1202 struct pci_dev *pdev = ts->base.pdev;
1203
1204 pci_set_power_state(pdev, PCI_D0);
1205 pci_restore_state(pdev);
1206 pci_enable_wake(pdev, PCI_D0, 0);
1207
1208 writel((u32 __force)PCI_D0, ts->ep_pmstate);
1209 dma_wmb();
1210 writel(TOPAZ_IPC_IRQ_WORD(TOPAZ_RC_PM_EP_IRQ),
1211 TOPAZ_LH_IPC4_INT(ts->base.sysctl_bar));
1212
1213 return 0;
1214 }
1215 #endif
1216
1217 struct qtnf_bus *qtnf_pcie_topaz_alloc(struct pci_dev *pdev)
1218 {
1219 struct qtnf_bus *bus;
1220 struct qtnf_pcie_topaz_state *ts;
1221
1222 bus = devm_kzalloc(&pdev->dev, sizeof(*bus) + sizeof(*ts), GFP_KERNEL);
1223 if (!bus)
1224 return NULL;
1225
1226 ts = get_bus_priv(bus);
1227 ts->base.probe_cb = qtnf_pcie_topaz_probe;
1228 ts->base.remove_cb = qtnf_pcie_topaz_remove;
1229 ts->base.dma_mask_get_cb = qtnf_topaz_dma_mask_get;
1230 #ifdef CONFIG_PM_SLEEP
1231 ts->base.resume_cb = qtnf_pcie_topaz_resume;
1232 ts->base.suspend_cb = qtnf_pcie_topaz_suspend;
1233 #endif
1234
1235 return bus;
1236 }
Linux with added FPC-III support