1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (c) 2011-2015 Xilinx Inc.
4 * Copyright (c) 2015, National Instruments Corp.
6 * FPGA Manager Driver for Xilinx Zynq, heavily based on xdevcfg driver
7 * in their vendor tree.
10 #include <linux/clk.h>
11 #include <linux/completion.h>
12 #include <linux/delay.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/fpga/fpga-mgr.h>
15 #include <linux/interrupt.h>
17 #include <linux/iopoll.h>
18 #include <linux/module.h>
19 #include <linux/mfd/syscon.h>
20 #include <linux/of_address.h>
21 #include <linux/of_irq.h>
23 #include <linux/regmap.h>
24 #include <linux/string.h>
25 #include <linux/scatterlist.h>
27 /* Offsets into SLCR regmap */
29 /* FPGA Software Reset Control */
30 #define SLCR_FPGA_RST_CTRL_OFFSET 0x240
31 /* Level Shifters Enable */
32 #define SLCR_LVL_SHFTR_EN_OFFSET 0x900
34 /* Constant Definitions */
36 /* Control Register */
37 #define CTRL_OFFSET 0x00
39 #define LOCK_OFFSET 0x04
40 /* Interrupt Status Register */
41 #define INT_STS_OFFSET 0x0c
42 /* Interrupt Mask Register */
43 #define INT_MASK_OFFSET 0x10
45 #define STATUS_OFFSET 0x14
46 /* DMA Source Address Register */
47 #define DMA_SRC_ADDR_OFFSET 0x18
48 /* DMA Destination Address Reg */
49 #define DMA_DST_ADDR_OFFSET 0x1c
50 /* DMA Source Transfer Length */
51 #define DMA_SRC_LEN_OFFSET 0x20
52 /* DMA Destination Transfer */
53 #define DMA_DEST_LEN_OFFSET 0x24
55 #define UNLOCK_OFFSET 0x34
56 /* Misc. Control Register */
57 #define MCTRL_OFFSET 0x80
59 /* Control Register Bit definitions */
61 /* Signal to reset FPGA */
62 #define CTRL_PCFG_PROG_B_MASK BIT(30)
63 /* Enable PCAP for PR */
64 #define CTRL_PCAP_PR_MASK BIT(27)
66 #define CTRL_PCAP_MODE_MASK BIT(26)
67 /* Lower rate to allow decrypt on the fly */
68 #define CTRL_PCAP_RATE_EN_MASK BIT(25)
69 /* System booted in secure mode */
70 #define CTRL_SEC_EN_MASK BIT(7)
72 /* Miscellaneous Control Register bit definitions */
73 /* Internal PCAP loopback */
74 #define MCTRL_PCAP_LPBK_MASK BIT(4)
76 /* Status register bit definitions */
78 /* FPGA init status */
79 #define STATUS_DMA_Q_F BIT(31)
80 #define STATUS_DMA_Q_E BIT(30)
81 #define STATUS_PCFG_INIT_MASK BIT(4)
83 /* Interrupt Status/Mask Register Bit definitions */
84 /* DMA command done */
85 #define IXR_DMA_DONE_MASK BIT(13)
86 /* DMA and PCAP cmd done */
87 #define IXR_D_P_DONE_MASK BIT(12)
89 #define IXR_PCFG_DONE_MASK BIT(2)
90 #define IXR_ERROR_FLAGS_MASK 0x00F0C860
91 #define IXR_ALL_MASK 0xF8F7F87F
93 /* Miscellaneous constant values */
95 /* Invalid DMA addr */
96 #define DMA_INVALID_ADDRESS GENMASK(31, 0)
97 /* Used to unlock the dev */
98 #define UNLOCK_MASK 0x757bdf0d
99 /* Timeout for polling reset bits */
100 #define INIT_POLL_TIMEOUT 2500000
101 /* Delay for polling reset bits */
102 #define INIT_POLL_DELAY 20
103 /* Signal this is the last DMA transfer, wait for the AXI and PCAP before
106 #define DMA_SRC_LAST_TRANSFER 1
107 /* Timeout for DMA completion */
108 #define DMA_TIMEOUT_MS 5000
110 /* Masks for controlling stuff in SLCR */
111 /* Disable all Level shifters */
112 #define LVL_SHFTR_DISABLE_ALL_MASK 0x0
113 /* Enable Level shifters from PS to PL */
114 #define LVL_SHFTR_ENABLE_PS_TO_PL 0xa
115 /* Enable Level shifters from PL to PS */
116 #define LVL_SHFTR_ENABLE_PL_TO_PS 0xf
117 /* Enable global resets */
118 #define FPGA_RST_ALL_MASK 0xf
119 /* Disable global resets */
120 #define FPGA_RST_NONE_MASK 0x0
122 struct zynq_fpga_priv {
126 void __iomem *io_base;
130 unsigned int dma_elm;
131 unsigned int dma_nelms;
132 struct scatterlist *cur_sg;
134 struct completion dma_done;
137 static inline void zynq_fpga_write(struct zynq_fpga_priv *priv, u32 offset,
140 writel(val, priv->io_base + offset);
143 static inline u32 zynq_fpga_read(const struct zynq_fpga_priv *priv,
146 return readl(priv->io_base + offset);
149 #define zynq_fpga_poll_timeout(priv, addr, val, cond, sleep_us, timeout_us) \
150 readl_poll_timeout(priv->io_base + addr, val, cond, sleep_us, \
153 /* Cause the specified irq mask bits to generate IRQs */
154 static inline void zynq_fpga_set_irq(struct zynq_fpga_priv *priv, u32 enable)
156 zynq_fpga_write(priv, INT_MASK_OFFSET, ~enable);
159 /* Must be called with dma_lock held */
160 static void zynq_step_dma(struct zynq_fpga_priv *priv)
166 first = priv->dma_elm == 0;
167 while (priv->cur_sg) {
168 /* Feed the DMA queue until it is full. */
169 if (zynq_fpga_read(priv, STATUS_OFFSET) & STATUS_DMA_Q_F)
172 addr = sg_dma_address(priv->cur_sg);
173 len = sg_dma_len(priv->cur_sg);
174 if (priv->dma_elm + 1 == priv->dma_nelms) {
175 /* The last transfer waits for the PCAP to finish too,
176 * notice this also changes the irq_mask to ignore
177 * IXR_DMA_DONE_MASK which ensures we do not trigger
178 * the completion too early.
180 addr |= DMA_SRC_LAST_TRANSFER;
183 priv->cur_sg = sg_next(priv->cur_sg);
187 zynq_fpga_write(priv, DMA_SRC_ADDR_OFFSET, addr);
188 zynq_fpga_write(priv, DMA_DST_ADDR_OFFSET, DMA_INVALID_ADDRESS);
189 zynq_fpga_write(priv, DMA_SRC_LEN_OFFSET, len / 4);
190 zynq_fpga_write(priv, DMA_DEST_LEN_OFFSET, 0);
193 /* Once the first transfer is queued we can turn on the ISR, future
194 * calls to zynq_step_dma will happen from the ISR context. The
195 * dma_lock spinlock guarantees this handover is done coherently, the
196 * ISR enable is put at the end to avoid another CPU spinning in the
199 if (first && priv->cur_sg) {
200 zynq_fpga_set_irq(priv,
201 IXR_DMA_DONE_MASK | IXR_ERROR_FLAGS_MASK);
202 } else if (!priv->cur_sg) {
203 /* The last transfer changes to DMA & PCAP mode since we do
204 * not want to continue until everything has been flushed into
207 zynq_fpga_set_irq(priv,
208 IXR_D_P_DONE_MASK | IXR_ERROR_FLAGS_MASK);
212 static irqreturn_t zynq_fpga_isr(int irq, void *data)
214 struct zynq_fpga_priv *priv = data;
217 /* If anything other than DMA completion is reported stop and hand
218 * control back to zynq_fpga_ops_write, something went wrong,
219 * otherwise progress the DMA.
221 spin_lock(&priv->dma_lock);
222 intr_status = zynq_fpga_read(priv, INT_STS_OFFSET);
223 if (!(intr_status & IXR_ERROR_FLAGS_MASK) &&
224 (intr_status & IXR_DMA_DONE_MASK) && priv->cur_sg) {
225 zynq_fpga_write(priv, INT_STS_OFFSET, IXR_DMA_DONE_MASK);
227 spin_unlock(&priv->dma_lock);
230 spin_unlock(&priv->dma_lock);
232 zynq_fpga_set_irq(priv, 0);
233 complete(&priv->dma_done);
238 /* Sanity check the proposed bitstream. It must start with the sync word in
239 * the correct byte order, and be dword aligned. The input is a Xilinx .bin
240 * file with every 32 bit quantity swapped.
242 static bool zynq_fpga_has_sync(const u8 *buf, size_t count)
244 for (; count >= 4; buf += 4, count -= 4)
245 if (buf[0] == 0x66 && buf[1] == 0x55 && buf[2] == 0x99 &&
251 static int zynq_fpga_ops_write_init(struct fpga_manager *mgr,
252 struct fpga_image_info *info,
253 const char *buf, size_t count)
255 struct zynq_fpga_priv *priv;
261 err = clk_enable(priv->clk);
265 /* check if bitstream is encrypted & and system's still secure */
266 if (info->flags & FPGA_MGR_ENCRYPTED_BITSTREAM) {
267 ctrl = zynq_fpga_read(priv, CTRL_OFFSET);
268 if (!(ctrl & CTRL_SEC_EN_MASK)) {
270 "System not secure, can't use encrypted bitstreams\n");
276 /* don't globally reset PL if we're doing partial reconfig */
277 if (!(info->flags & FPGA_MGR_PARTIAL_RECONFIG)) {
278 if (!zynq_fpga_has_sync(buf, count)) {
280 "Invalid bitstream, could not find a sync word. Bitstream must be a byte swapped .bin file\n");
285 /* assert AXI interface resets */
286 regmap_write(priv->slcr, SLCR_FPGA_RST_CTRL_OFFSET,
289 /* disable all level shifters */
290 regmap_write(priv->slcr, SLCR_LVL_SHFTR_EN_OFFSET,
291 LVL_SHFTR_DISABLE_ALL_MASK);
292 /* enable level shifters from PS to PL */
293 regmap_write(priv->slcr, SLCR_LVL_SHFTR_EN_OFFSET,
294 LVL_SHFTR_ENABLE_PS_TO_PL);
296 /* create a rising edge on PCFG_INIT. PCFG_INIT follows
297 * PCFG_PROG_B, so we need to poll it after setting PCFG_PROG_B
298 * to make sure the rising edge actually happens.
299 * Note: PCFG_PROG_B is low active, sequence as described in
300 * UG585 v1.10 page 211
302 ctrl = zynq_fpga_read(priv, CTRL_OFFSET);
303 ctrl |= CTRL_PCFG_PROG_B_MASK;
305 zynq_fpga_write(priv, CTRL_OFFSET, ctrl);
307 err = zynq_fpga_poll_timeout(priv, STATUS_OFFSET, status,
308 status & STATUS_PCFG_INIT_MASK,
312 dev_err(&mgr->dev, "Timeout waiting for PCFG_INIT\n");
316 ctrl = zynq_fpga_read(priv, CTRL_OFFSET);
317 ctrl &= ~CTRL_PCFG_PROG_B_MASK;
319 zynq_fpga_write(priv, CTRL_OFFSET, ctrl);
321 err = zynq_fpga_poll_timeout(priv, STATUS_OFFSET, status,
322 !(status & STATUS_PCFG_INIT_MASK),
326 dev_err(&mgr->dev, "Timeout waiting for !PCFG_INIT\n");
330 ctrl = zynq_fpga_read(priv, CTRL_OFFSET);
331 ctrl |= CTRL_PCFG_PROG_B_MASK;
333 zynq_fpga_write(priv, CTRL_OFFSET, ctrl);
335 err = zynq_fpga_poll_timeout(priv, STATUS_OFFSET, status,
336 status & STATUS_PCFG_INIT_MASK,
340 dev_err(&mgr->dev, "Timeout waiting for PCFG_INIT\n");
345 /* set configuration register with following options:
346 * - enable PCAP interface
347 * - set throughput for maximum speed (if bistream not encrypted)
348 * - set CPU in user mode
350 ctrl = zynq_fpga_read(priv, CTRL_OFFSET);
351 if (info->flags & FPGA_MGR_ENCRYPTED_BITSTREAM)
352 zynq_fpga_write(priv, CTRL_OFFSET,
353 (CTRL_PCAP_PR_MASK | CTRL_PCAP_MODE_MASK
354 | CTRL_PCAP_RATE_EN_MASK | ctrl));
356 zynq_fpga_write(priv, CTRL_OFFSET,
357 (CTRL_PCAP_PR_MASK | CTRL_PCAP_MODE_MASK
361 /* We expect that the command queue is empty right now. */
362 status = zynq_fpga_read(priv, STATUS_OFFSET);
363 if ((status & STATUS_DMA_Q_F) ||
364 (status & STATUS_DMA_Q_E) != STATUS_DMA_Q_E) {
365 dev_err(&mgr->dev, "DMA command queue not right\n");
370 /* ensure internal PCAP loopback is disabled */
371 ctrl = zynq_fpga_read(priv, MCTRL_OFFSET);
372 zynq_fpga_write(priv, MCTRL_OFFSET, (~MCTRL_PCAP_LPBK_MASK & ctrl));
374 clk_disable(priv->clk);
379 clk_disable(priv->clk);
384 static int zynq_fpga_ops_write(struct fpga_manager *mgr, struct sg_table *sgt)
386 struct zynq_fpga_priv *priv;
390 unsigned long timeout;
392 struct scatterlist *sg;
397 /* The hardware can only DMA multiples of 4 bytes, and it requires the
398 * starting addresses to be aligned to 64 bits (UG585 pg 212).
400 for_each_sg(sgt->sgl, sg, sgt->nents, i) {
401 if ((sg->offset % 8) || (sg->length % 4)) {
403 "Invalid bitstream, chunks must be aligned\n");
409 dma_map_sg(mgr->dev.parent, sgt->sgl, sgt->nents, DMA_TO_DEVICE);
410 if (priv->dma_nelms == 0) {
411 dev_err(&mgr->dev, "Unable to DMA map (TO_DEVICE)\n");
416 err = clk_enable(priv->clk);
420 zynq_fpga_write(priv, INT_STS_OFFSET, IXR_ALL_MASK);
421 reinit_completion(&priv->dma_done);
423 /* zynq_step_dma will turn on interrupts */
424 spin_lock_irqsave(&priv->dma_lock, flags);
426 priv->cur_sg = sgt->sgl;
428 spin_unlock_irqrestore(&priv->dma_lock, flags);
430 timeout = wait_for_completion_timeout(&priv->dma_done,
431 msecs_to_jiffies(DMA_TIMEOUT_MS));
433 spin_lock_irqsave(&priv->dma_lock, flags);
434 zynq_fpga_set_irq(priv, 0);
436 spin_unlock_irqrestore(&priv->dma_lock, flags);
438 intr_status = zynq_fpga_read(priv, INT_STS_OFFSET);
439 zynq_fpga_write(priv, INT_STS_OFFSET, IXR_ALL_MASK);
441 /* There doesn't seem to be a way to force cancel any DMA, so if
442 * something went wrong we are relying on the hardware to have halted
443 * the DMA before we get here, if there was we could use
444 * wait_for_completion_interruptible too.
447 if (intr_status & IXR_ERROR_FLAGS_MASK) {
448 why = "DMA reported error";
454 !((intr_status & IXR_D_P_DONE_MASK) == IXR_D_P_DONE_MASK)) {
456 why = "DMA timed out";
458 why = "DMA did not complete";
468 "%s: INT_STS:0x%x CTRL:0x%x LOCK:0x%x INT_MASK:0x%x STATUS:0x%x MCTRL:0x%x\n",
471 zynq_fpga_read(priv, CTRL_OFFSET),
472 zynq_fpga_read(priv, LOCK_OFFSET),
473 zynq_fpga_read(priv, INT_MASK_OFFSET),
474 zynq_fpga_read(priv, STATUS_OFFSET),
475 zynq_fpga_read(priv, MCTRL_OFFSET));
478 clk_disable(priv->clk);
481 dma_unmap_sg(mgr->dev.parent, sgt->sgl, sgt->nents, DMA_TO_DEVICE);
485 static int zynq_fpga_ops_write_complete(struct fpga_manager *mgr,
486 struct fpga_image_info *info)
488 struct zynq_fpga_priv *priv = mgr->priv;
492 err = clk_enable(priv->clk);
496 /* Release 'PR' control back to the ICAP */
497 zynq_fpga_write(priv, CTRL_OFFSET,
498 zynq_fpga_read(priv, CTRL_OFFSET) & ~CTRL_PCAP_PR_MASK);
500 err = zynq_fpga_poll_timeout(priv, INT_STS_OFFSET, intr_status,
501 intr_status & IXR_PCFG_DONE_MASK,
505 clk_disable(priv->clk);
510 /* for the partial reconfig case we didn't touch the level shifters */
511 if (!(info->flags & FPGA_MGR_PARTIAL_RECONFIG)) {
512 /* enable level shifters from PL to PS */
513 regmap_write(priv->slcr, SLCR_LVL_SHFTR_EN_OFFSET,
514 LVL_SHFTR_ENABLE_PL_TO_PS);
516 /* deassert AXI interface resets */
517 regmap_write(priv->slcr, SLCR_FPGA_RST_CTRL_OFFSET,
524 static enum fpga_mgr_states zynq_fpga_ops_state(struct fpga_manager *mgr)
528 struct zynq_fpga_priv *priv;
532 err = clk_enable(priv->clk);
534 return FPGA_MGR_STATE_UNKNOWN;
536 intr_status = zynq_fpga_read(priv, INT_STS_OFFSET);
537 clk_disable(priv->clk);
539 if (intr_status & IXR_PCFG_DONE_MASK)
540 return FPGA_MGR_STATE_OPERATING;
542 return FPGA_MGR_STATE_UNKNOWN;
545 static const struct fpga_manager_ops zynq_fpga_ops = {
546 .initial_header_size = 128,
547 .state = zynq_fpga_ops_state,
548 .write_init = zynq_fpga_ops_write_init,
549 .write_sg = zynq_fpga_ops_write,
550 .write_complete = zynq_fpga_ops_write_complete,
553 static int zynq_fpga_probe(struct platform_device *pdev)
555 struct device *dev = &pdev->dev;
556 struct zynq_fpga_priv *priv;
557 struct fpga_manager *mgr;
558 struct resource *res;
561 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
564 spin_lock_init(&priv->dma_lock);
566 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
567 priv->io_base = devm_ioremap_resource(dev, res);
568 if (IS_ERR(priv->io_base))
569 return PTR_ERR(priv->io_base);
571 priv->slcr = syscon_regmap_lookup_by_phandle(dev->of_node,
573 if (IS_ERR(priv->slcr)) {
574 dev_err(dev, "unable to get zynq-slcr regmap\n");
575 return PTR_ERR(priv->slcr);
578 init_completion(&priv->dma_done);
580 priv->irq = platform_get_irq(pdev, 0);
584 priv->clk = devm_clk_get(dev, "ref_clk");
585 if (IS_ERR(priv->clk)) {
586 if (PTR_ERR(priv->clk) != -EPROBE_DEFER)
587 dev_err(dev, "input clock not found\n");
588 return PTR_ERR(priv->clk);
591 err = clk_prepare_enable(priv->clk);
593 dev_err(dev, "unable to enable clock\n");
597 /* unlock the device */
598 zynq_fpga_write(priv, UNLOCK_OFFSET, UNLOCK_MASK);
600 zynq_fpga_set_irq(priv, 0);
601 zynq_fpga_write(priv, INT_STS_OFFSET, IXR_ALL_MASK);
602 err = devm_request_irq(dev, priv->irq, zynq_fpga_isr, 0, dev_name(dev),
605 dev_err(dev, "unable to request IRQ\n");
606 clk_disable_unprepare(priv->clk);
610 clk_disable(priv->clk);
612 mgr = devm_fpga_mgr_create(dev, "Xilinx Zynq FPGA Manager",
613 &zynq_fpga_ops, priv);
617 platform_set_drvdata(pdev, mgr);
619 err = fpga_mgr_register(mgr);
621 dev_err(dev, "unable to register FPGA manager\n");
622 clk_unprepare(priv->clk);
629 static int zynq_fpga_remove(struct platform_device *pdev)
631 struct zynq_fpga_priv *priv;
632 struct fpga_manager *mgr;
634 mgr = platform_get_drvdata(pdev);
637 fpga_mgr_unregister(mgr);
639 clk_unprepare(priv->clk);
645 static const struct of_device_id zynq_fpga_of_match[] = {
646 { .compatible = "xlnx,zynq-devcfg-1.0", },
650 MODULE_DEVICE_TABLE(of, zynq_fpga_of_match);
653 static struct platform_driver zynq_fpga_driver = {
654 .probe = zynq_fpga_probe,
655 .remove = zynq_fpga_remove,
657 .name = "zynq_fpga_manager",
658 .of_match_table = of_match_ptr(zynq_fpga_of_match),
662 module_platform_driver(zynq_fpga_driver);
664 MODULE_AUTHOR("Moritz Fischer <moritz.fischer@ettus.com>");
665 MODULE_AUTHOR("Michal Simek <michal.simek@xilinx.com>");
666 MODULE_DESCRIPTION("Xilinx Zynq FPGA Manager");
667 MODULE_LICENSE("GPL v2");