// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (c) 2011-2015 Xilinx Inc. * Copyright (c) 2015, National Instruments Corp. * * FPGA Manager Driver for Xilinx Zynq, heavily based on xdevcfg driver * in their vendor tree. */ #include <linux/clk.h> #include <linux/completion.h> #include <linux/delay.h> #include <linux/dma-mapping.h> #include <linux/fpga/fpga-mgr.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/iopoll.h> #include <linux/module.h> #include <linux/mfd/syscon.h> #include <linux/of_address.h> #include <linux/of_irq.h> #include <linux/pm.h> #include <linux/regmap.h> #include <linux/string.h> #include <linux/scatterlist.h> /* Offsets into SLCR regmap */ /* FPGA Software Reset Control */ #define SLCR_FPGA_RST_CTRL_OFFSET 0x240 /* Level Shifters Enable */ #define SLCR_LVL_SHFTR_EN_OFFSET 0x900 /* Constant Definitions */ /* Control Register */ #define CTRL_OFFSET 0x00 /* Lock Register */ #define LOCK_OFFSET 0x04 /* Interrupt Status Register */ #define INT_STS_OFFSET 0x0c /* Interrupt Mask Register */ #define INT_MASK_OFFSET 0x10 /* Status Register */ #define STATUS_OFFSET 0x14 /* DMA Source Address Register */ #define DMA_SRC_ADDR_OFFSET 0x18 /* DMA Destination Address Reg */ #define DMA_DST_ADDR_OFFSET 0x1c /* DMA Source Transfer Length */ #define DMA_SRC_LEN_OFFSET 0x20 /* DMA Destination Transfer */ #define DMA_DEST_LEN_OFFSET 0x24 /* Unlock Register */ #define UNLOCK_OFFSET 0x34 /* Misc. Control Register */ #define MCTRL_OFFSET 0x80 /* Control Register Bit definitions */ /* Signal to reset FPGA */ #define CTRL_PCFG_PROG_B_MASK BIT(30) /* Enable PCAP for PR */ #define CTRL_PCAP_PR_MASK BIT(27) /* Enable PCAP */ #define CTRL_PCAP_MODE_MASK BIT(26) /* Lower rate to allow decrypt on the fly */ #define CTRL_PCAP_RATE_EN_MASK BIT(25) /* System booted in secure mode */ #define CTRL_SEC_EN_MASK BIT(7) /* Miscellaneous Control Register bit definitions */ /* Internal PCAP loopback */ #define MCTRL_PCAP_LPBK_MASK BIT(4) /* Status register bit definitions */ /* FPGA init status */ #define STATUS_DMA_Q_F BIT(31) #define STATUS_DMA_Q_E BIT(30) #define STATUS_PCFG_INIT_MASK BIT(4) /* Interrupt Status/Mask Register Bit definitions */ /* DMA command done */ #define IXR_DMA_DONE_MASK BIT(13) /* DMA and PCAP cmd done */ #define IXR_D_P_DONE_MASK BIT(12) /* FPGA programmed */ #define IXR_PCFG_DONE_MASK BIT(2) #define IXR_ERROR_FLAGS_MASK 0x00F0C860 #define IXR_ALL_MASK 0xF8F7F87F /* Miscellaneous constant values */ /* Invalid DMA addr */ #define DMA_INVALID_ADDRESS GENMASK(31, 0) /* Used to unlock the dev */ #define UNLOCK_MASK 0x757bdf0d /* Timeout for polling reset bits */ #define INIT_POLL_TIMEOUT 2500000 /* Delay for polling reset bits */ #define INIT_POLL_DELAY 20 /* Signal this is the last DMA transfer, wait for the AXI and PCAP before * interrupting */ #define DMA_SRC_LAST_TRANSFER 1 /* Timeout for DMA completion */ #define DMA_TIMEOUT_MS 5000 /* Masks for controlling stuff in SLCR */ /* Disable all Level shifters */ #define LVL_SHFTR_DISABLE_ALL_MASK 0x0 /* Enable Level shifters from PS to PL */ #define LVL_SHFTR_ENABLE_PS_TO_PL 0xa /* Enable Level shifters from PL to PS */ #define LVL_SHFTR_ENABLE_PL_TO_PS 0xf /* Enable global resets */ #define FPGA_RST_ALL_MASK 0xf /* Disable global resets */ #define FPGA_RST_NONE_MASK 0x0 struct zynq_fpga_priv { int irq; struct clk *clk; void __iomem *io_base; struct regmap *slcr; spinlock_t dma_lock; unsigned int dma_elm; unsigned int dma_nelms; struct scatterlist *cur_sg; struct completion dma_done; }; static inline void zynq_fpga_write(struct zynq_fpga_priv *priv, u32 offset, u32 val) { writel(val, priv->io_base + offset); } static inline u32 zynq_fpga_read(const struct zynq_fpga_priv *priv, u32 offset) { return readl(priv->io_base + offset); } #define zynq_fpga_poll_timeout(priv, addr, val, cond, sleep_us, timeout_us) \ readl_poll_timeout(priv->io_base + addr, val, cond, sleep_us, \ timeout_us) /* Cause the specified irq mask bits to generate IRQs */ static inline void zynq_fpga_set_irq(struct zynq_fpga_priv *priv, u32 enable) { zynq_fpga_write(priv, INT_MASK_OFFSET, ~enable); } /* Must be called with dma_lock held */ static void zynq_step_dma(struct zynq_fpga_priv *priv) { u32 addr; u32 len; bool first; first = priv->dma_elm == 0; while (priv->cur_sg) { /* Feed the DMA queue until it is full. */ if (zynq_fpga_read(priv, STATUS_OFFSET) & STATUS_DMA_Q_F) break; addr = sg_dma_address(priv->cur_sg); len = sg_dma_len(priv->cur_sg); if (priv->dma_elm + 1 == priv->dma_nelms) { /* The last transfer waits for the PCAP to finish too, * notice this also changes the irq_mask to ignore * IXR_DMA_DONE_MASK which ensures we do not trigger * the completion too early. */ addr |= DMA_SRC_LAST_TRANSFER; priv->cur_sg = NULL; } else { priv->cur_sg = sg_next(priv->cur_sg); priv->dma_elm++; } zynq_fpga_write(priv, DMA_SRC_ADDR_OFFSET, addr); zynq_fpga_write(priv, DMA_DST_ADDR_OFFSET, DMA_INVALID_ADDRESS); zynq_fpga_write(priv, DMA_SRC_LEN_OFFSET, len / 4); zynq_fpga_write(priv, DMA_DEST_LEN_OFFSET, 0); } /* Once the first transfer is queued we can turn on the ISR, future * calls to zynq_step_dma will happen from the ISR context. The * dma_lock spinlock guarantees this handover is done coherently, the * ISR enable is put at the end to avoid another CPU spinning in the * ISR on this lock. */ if (first && priv->cur_sg) { zynq_fpga_set_irq(priv, IXR_DMA_DONE_MASK | IXR_ERROR_FLAGS_MASK); } else if (!priv->cur_sg) { /* The last transfer changes to DMA & PCAP mode since we do * not want to continue until everything has been flushed into * the PCAP. */ zynq_fpga_set_irq(priv, IXR_D_P_DONE_MASK | IXR_ERROR_FLAGS_MASK); } } static irqreturn_t zynq_fpga_isr(int irq, void *data) { struct zynq_fpga_priv *priv = data; u32 intr_status; /* If anything other than DMA completion is reported stop and hand * control back to zynq_fpga_ops_write, something went wrong, * otherwise progress the DMA. */ spin_lock(&priv->dma_lock); intr_status = zynq_fpga_read(priv, INT_STS_OFFSET); if (!(intr_status & IXR_ERROR_FLAGS_MASK) && (intr_status & IXR_DMA_DONE_MASK) && priv->cur_sg) { zynq_fpga_write(priv, INT_STS_OFFSET, IXR_DMA_DONE_MASK); zynq_step_dma(priv); spin_unlock(&priv->dma_lock); return IRQ_HANDLED; } spin_unlock(&priv->dma_lock); zynq_fpga_set_irq(priv, 0); complete(&priv->dma_done); return IRQ_HANDLED; } /* Sanity check the proposed bitstream. It must start with the sync word in * the correct byte order, and be dword aligned. The input is a Xilinx .bin * file with every 32 bit quantity swapped. */ static bool zynq_fpga_has_sync(const u8 *buf, size_t count) { for (; count >= 4; buf += 4, count -= 4) if (buf[0] == 0x66 && buf[1] == 0x55 && buf[2] == 0x99 && buf[3] == 0xaa) return true; return false; } static int zynq_fpga_ops_write_init(struct fpga_manager *mgr, struct fpga_image_info *info, const char *buf, size_t count) { struct zynq_fpga_priv *priv; u32 ctrl, status; int err; priv = mgr->priv; err = clk_enable(priv->clk); if (err) return err; /* check if bitstream is encrypted & and system's still secure */ if (info->flags & FPGA_MGR_ENCRYPTED_BITSTREAM) { ctrl = zynq_fpga_read(priv, CTRL_OFFSET); if (!(ctrl & CTRL_SEC_EN_MASK)) { dev_err(&mgr->dev, "System not secure, can't use encrypted bitstreams\n"); err = -EINVAL; goto out_err; } } /* don't globally reset PL if we're doing partial reconfig */ if (!(info->flags & FPGA_MGR_PARTIAL_RECONFIG)) { if (!zynq_fpga_has_sync(buf, count)) { dev_err(&mgr->dev, "Invalid bitstream, could not find a sync word. Bitstream must be a byte swapped .bin file\n"); err = -EINVAL; goto out_err; } /* assert AXI interface resets */ regmap_write(priv->slcr, SLCR_FPGA_RST_CTRL_OFFSET, FPGA_RST_ALL_MASK); /* disable all level shifters */ regmap_write(priv->slcr, SLCR_LVL_SHFTR_EN_OFFSET, LVL_SHFTR_DISABLE_ALL_MASK); /* enable level shifters from PS to PL */ regmap_write(priv->slcr, SLCR_LVL_SHFTR_EN_OFFSET, LVL_SHFTR_ENABLE_PS_TO_PL); /* create a rising edge on PCFG_INIT. PCFG_INIT follows * PCFG_PROG_B, so we need to poll it after setting PCFG_PROG_B * to make sure the rising edge actually happens. * Note: PCFG_PROG_B is low active, sequence as described in * UG585 v1.10 page 211 */ ctrl = zynq_fpga_read(priv, CTRL_OFFSET); ctrl |= CTRL_PCFG_PROG_B_MASK; zynq_fpga_write(priv, CTRL_OFFSET, ctrl); err = zynq_fpga_poll_timeout(priv, STATUS_OFFSET, status, status & STATUS_PCFG_INIT_MASK, INIT_POLL_DELAY, INIT_POLL_TIMEOUT); if (err) { dev_err(&mgr->dev, "Timeout waiting for PCFG_INIT\n"); goto out_err; } ctrl = zynq_fpga_read(priv, CTRL_OFFSET); ctrl &= ~CTRL_PCFG_PROG_B_MASK; zynq_fpga_write(priv, CTRL_OFFSET, ctrl); err = zynq_fpga_poll_timeout(priv, STATUS_OFFSET, status, !(status & STATUS_PCFG_INIT_MASK), INIT_POLL_DELAY, INIT_POLL_TIMEOUT); if (err) { dev_err(&mgr->dev, "Timeout waiting for !PCFG_INIT\n"); goto out_err; } ctrl = zynq_fpga_read(priv, CTRL_OFFSET); ctrl |= CTRL_PCFG_PROG_B_MASK; zynq_fpga_write(priv, CTRL_OFFSET, ctrl); err = zynq_fpga_poll_timeout(priv, STATUS_OFFSET, status, status & STATUS_PCFG_INIT_MASK, INIT_POLL_DELAY, INIT_POLL_TIMEOUT); if (err) { dev_err(&mgr->dev, "Timeout waiting for PCFG_INIT\n"); goto out_err; } } /* set configuration register with following options: * - enable PCAP interface * - set throughput for maximum speed (if bistream not encrypted) * - set CPU in user mode */ ctrl = zynq_fpga_read(priv, CTRL_OFFSET); if (info->flags & FPGA_MGR_ENCRYPTED_BITSTREAM) zynq_fpga_write(priv, CTRL_OFFSET, (CTRL_PCAP_PR_MASK | CTRL_PCAP_MODE_MASK | CTRL_PCAP_RATE_EN_MASK | ctrl)); else zynq_fpga_write(priv, CTRL_OFFSET, (CTRL_PCAP_PR_MASK | CTRL_PCAP_MODE_MASK | ctrl)); /* We expect that the command queue is empty right now. */ status = zynq_fpga_read(priv, STATUS_OFFSET); if ((status & STATUS_DMA_Q_F) || (status & STATUS_DMA_Q_E) != STATUS_DMA_Q_E) { dev_err(&mgr->dev, "DMA command queue not right\n"); err = -EBUSY; goto out_err; } /* ensure internal PCAP loopback is disabled */ ctrl = zynq_fpga_read(priv, MCTRL_OFFSET); zynq_fpga_write(priv, MCTRL_OFFSET, (~MCTRL_PCAP_LPBK_MASK & ctrl)); clk_disable(priv->clk); return 0; out_err: clk_disable(priv->clk); return err; } static int zynq_fpga_ops_write(struct fpga_manager *mgr, struct sg_table *sgt) { struct zynq_fpga_priv *priv; const char *why; int err; u32 intr_status; unsigned long timeout; unsigned long flags; struct scatterlist *sg; int i; priv = mgr->priv; /* The hardware can only DMA multiples of 4 bytes, and it requires the * starting addresses to be aligned to 64 bits (UG585 pg 212). */ for_each_sg(sgt->sgl, sg, sgt->nents, i) { if ((sg->offset % 8) || (sg->length % 4)) { dev_err(&mgr->dev, "Invalid bitstream, chunks must be aligned\n"); return -EINVAL; } } priv->dma_nelms = dma_map_sg(mgr->dev.parent, sgt->sgl, sgt->nents, DMA_TO_DEVICE); if (priv->dma_nelms == 0) { dev_err(&mgr->dev, "Unable to DMA map (TO_DEVICE)\n"); return -ENOMEM; } /* enable clock */ err = clk_enable(priv->clk); if (err) goto out_free; zynq_fpga_write(priv, INT_STS_OFFSET, IXR_ALL_MASK); reinit_completion(&priv->dma_done); /* zynq_step_dma will turn on interrupts */ spin_lock_irqsave(&priv->dma_lock, flags); priv->dma_elm = 0; priv->cur_sg = sgt->sgl; zynq_step_dma(priv); spin_unlock_irqrestore(&priv->dma_lock, flags); timeout = wait_for_completion_timeout(&priv->dma_done, msecs_to_jiffies(DMA_TIMEOUT_MS)); spin_lock_irqsave(&priv->dma_lock, flags); zynq_fpga_set_irq(priv, 0); priv->cur_sg = NULL; spin_unlock_irqrestore(&priv->dma_lock, flags); intr_status = zynq_fpga_read(priv, INT_STS_OFFSET); zynq_fpga_write(priv, INT_STS_OFFSET, IXR_ALL_MASK); /* There doesn't seem to be a way to force cancel any DMA, so if * something went wrong we are relying on the hardware to have halted * the DMA before we get here, if there was we could use * wait_for_completion_interruptible too. */ if (intr_status & IXR_ERROR_FLAGS_MASK) { why = "DMA reported error"; err = -EIO; goto out_report; } if (priv->cur_sg || !((intr_status & IXR_D_P_DONE_MASK) == IXR_D_P_DONE_MASK)) { if (timeout == 0) why = "DMA timed out"; else why = "DMA did not complete"; err = -EIO; goto out_report; } err = 0; goto out_clk; out_report: dev_err(&mgr->dev, "%s: INT_STS:0x%x CTRL:0x%x LOCK:0x%x INT_MASK:0x%x STATUS:0x%x MCTRL:0x%x\n", why, intr_status, zynq_fpga_read(priv, CTRL_OFFSET), zynq_fpga_read(priv, LOCK_OFFSET), zynq_fpga_read(priv, INT_MASK_OFFSET), zynq_fpga_read(priv, STATUS_OFFSET), zynq_fpga_read(priv, MCTRL_OFFSET)); out_clk: clk_disable(priv->clk); out_free: dma_unmap_sg(mgr->dev.parent, sgt->sgl, sgt->nents, DMA_TO_DEVICE); return err; } static int zynq_fpga_ops_write_complete(struct fpga_manager *mgr, struct fpga_image_info *info) { struct zynq_fpga_priv *priv = mgr->priv; int err; u32 intr_status; err = clk_enable(priv->clk); if (err) return err; err = zynq_fpga_poll_timeout(priv, INT_STS_OFFSET, intr_status, intr_status & IXR_PCFG_DONE_MASK, INIT_POLL_DELAY, INIT_POLL_TIMEOUT); /* Release 'PR' control back to the ICAP */ zynq_fpga_write(priv, CTRL_OFFSET, zynq_fpga_read(priv, CTRL_OFFSET) & ~CTRL_PCAP_PR_MASK); clk_disable(priv->clk); if (err) return err; /* for the partial reconfig case we didn't touch the level shifters */ if (!(info->flags & FPGA_MGR_PARTIAL_RECONFIG)) { /* enable level shifters from PL to PS */ regmap_write(priv->slcr, SLCR_LVL_SHFTR_EN_OFFSET, LVL_SHFTR_ENABLE_PL_TO_PS); /* deassert AXI interface resets */ regmap_write(priv->slcr, SLCR_FPGA_RST_CTRL_OFFSET, FPGA_RST_NONE_MASK); } return 0; } static enum fpga_mgr_states zynq_fpga_ops_state(struct fpga_manager *mgr) { int err; u32 intr_status; struct zynq_fpga_priv *priv; priv = mgr->priv; err = clk_enable(priv->clk); if (err) return FPGA_MGR_STATE_UNKNOWN; intr_status = zynq_fpga_read(priv, INT_STS_OFFSET); clk_disable(priv->clk); if (intr_status & IXR_PCFG_DONE_MASK) return FPGA_MGR_STATE_OPERATING; return FPGA_MGR_STATE_UNKNOWN; } static const struct fpga_manager_ops zynq_fpga_ops = { .initial_header_size = 128, .state = zynq_fpga_ops_state, .write_init = zynq_fpga_ops_write_init, .write_sg = zynq_fpga_ops_write, .write_complete = zynq_fpga_ops_write_complete, }; static int zynq_fpga_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct zynq_fpga_priv *priv; struct fpga_manager *mgr; struct resource *res; int err; priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; spin_lock_init(&priv->dma_lock); res = platform_get_resource(pdev, IORESOURCE_MEM, 0); priv->io_base = devm_ioremap_resource(dev, res); if (IS_ERR(priv->io_base)) return PTR_ERR(priv->io_base); priv->slcr = syscon_regmap_lookup_by_phandle(dev->of_node, "syscon"); if (IS_ERR(priv->slcr)) { dev_err(dev, "unable to get zynq-slcr regmap\n"); return PTR_ERR(priv->slcr); } init_completion(&priv->dma_done); priv->irq = platform_get_irq(pdev, 0); if (priv->irq < 0) return priv->irq; priv->clk = devm_clk_get(dev, "ref_clk"); if (IS_ERR(priv->clk)) return dev_err_probe(dev, PTR_ERR(priv->clk), "input clock not found\n"); err = clk_prepare_enable(priv->clk); if (err) { dev_err(dev, "unable to enable clock\n"); return err; } /* unlock the device */ zynq_fpga_write(priv, UNLOCK_OFFSET, UNLOCK_MASK); zynq_fpga_set_irq(priv, 0); zynq_fpga_write(priv, INT_STS_OFFSET, IXR_ALL_MASK); err = devm_request_irq(dev, priv->irq, zynq_fpga_isr, 0, dev_name(dev), priv); if (err) { dev_err(dev, "unable to request IRQ\n"); clk_disable_unprepare(priv->clk); return err; } clk_disable(priv->clk); mgr = fpga_mgr_register(dev, "Xilinx Zynq FPGA Manager", &zynq_fpga_ops, priv); if (IS_ERR(mgr)) { dev_err(dev, "unable to register FPGA manager\n"); clk_unprepare(priv->clk); return PTR_ERR(mgr); } platform_set_drvdata(pdev, mgr); return 0; } static int zynq_fpga_remove(struct platform_device *pdev) { struct zynq_fpga_priv *priv; struct fpga_manager *mgr; mgr = platform_get_drvdata(pdev); priv = mgr->priv; fpga_mgr_unregister(mgr); clk_unprepare(priv->clk); return 0; } #ifdef CONFIG_OF static const struct of_device_id zynq_fpga_of_match[] = { { .compatible = "xlnx,zynq-devcfg-1.0", }, {}, }; MODULE_DEVICE_TABLE(of, zynq_fpga_of_match); #endif static struct platform_driver zynq_fpga_driver = { .probe = zynq_fpga_probe, .remove = zynq_fpga_remove, .driver = { .name = "zynq_fpga_manager", .of_match_table = of_match_ptr(zynq_fpga_of_match), }, }; module_platform_driver(zynq_fpga_driver); MODULE_AUTHOR("Moritz Fischer <moritz.fischer@ettus.com>"); MODULE_AUTHOR("Michal Simek <michal.simek@xilinx.com>"); MODULE_DESCRIPTION("Xilinx Zynq FPGA Manager"); MODULE_LICENSE("GPL v2");