On 4/27/21 1:54 PM, Lizhi Hou wrote:
ICAP stands for Hardware Internal Configuration Access Port. ICAP is discovered by walking the firmware metadata. A xrt device node will be created for it. FPGA bitstream is written to hardware through ICAP. Signed-off-by: Sonal Santan <sonal.santan@xxxxxxxxxx> Signed-off-by: Max Zhen <max.zhen@xxxxxxxxxx> Signed-off-by: Lizhi Hou <lizhi.hou@xxxxxxxxxx> --- drivers/fpga/xrt/include/xleaf/icap.h | 27 +++ drivers/fpga/xrt/lib/xleaf/icap.c | 328 ++++++++++++++++++++++++++ 2 files changed, 355 insertions(+) create mode 100644 drivers/fpga/xrt/include/xleaf/icap.h create mode 100644 drivers/fpga/xrt/lib/xleaf/icap.c diff --git a/drivers/fpga/xrt/include/xleaf/icap.h b/drivers/fpga/xrt/include/xleaf/icap.h new file mode 100644 index 000000000000..96d39a8934fa --- /dev/null +++ b/drivers/fpga/xrt/include/xleaf/icap.h @@ -0,0 +1,27 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2020-2021 Xilinx, Inc. + * + * Authors: + * Lizhi Hou <Lizhi.Hou@xxxxxxxxxx> + */ + +#ifndef _XRT_ICAP_H_ +#define _XRT_ICAP_H_ + +#include "xleaf.h" + +/* + * ICAP driver leaf calls. + */ +enum xrt_icap_leaf_cmd { + XRT_ICAP_WRITE = XRT_XLEAF_CUSTOM_BASE, /* See comments in xleaf.h */ + XRT_ICAP_GET_IDCODE, +}; + +struct xrt_icap_wr { + void *xiiw_bit_data; + u32 xiiw_data_len; +}; + +#endif /* _XRT_ICAP_H_ */ diff --git a/drivers/fpga/xrt/lib/xleaf/icap.c b/drivers/fpga/xrt/lib/xleaf/icap.c new file mode 100644 index 000000000000..755ea2fc0e75 --- /dev/null +++ b/drivers/fpga/xrt/lib/xleaf/icap.c @@ -0,0 +1,328 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Xilinx Alveo FPGA ICAP Driver + * + * Copyright (C) 2020-2021 Xilinx, Inc. + * + * Authors: + * Lizhi Hou<Lizhi.Hou@xxxxxxxxxx> + * Sonal Santan <sonals@xxxxxxxxxx> + * Max Zhen <maxz@xxxxxxxxxx> + */ + +#include <linux/mod_devicetable.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/regmap.h> +#include <linux/io.h> +#include "metadata.h" +#include "xleaf.h" +#include "xleaf/icap.h" +#include "xclbin-helper.h" + +#define XRT_ICAP "xrt_icap" + +#define ICAP_ERR(icap, fmt, arg...) \ + xrt_err((icap)->xdev, fmt "\n", ##arg) +#define ICAP_WARN(icap, fmt, arg...) \ + xrt_warn((icap)->xdev, fmt "\n", ##arg) +#define ICAP_INFO(icap, fmt, arg...) \ + xrt_info((icap)->xdev, fmt "\n", ##arg) +#define ICAP_DBG(icap, fmt, arg...) \ + xrt_dbg((icap)->xdev, fmt "\n", ##arg) + +/* + * AXI-HWICAP IP register layout. Please see + * https://www.xilinx.com/support/documentation/ip_documentation/axi_hwicap/v3_0/pg134-axi-hwicap.pdf + */ +#define ICAP_REG_GIER 0x1C +#define ICAP_REG_ISR 0x20 +#define ICAP_REG_IER 0x28 +#define ICAP_REG_WF 0x100 +#define ICAP_REG_RF 0x104 +#define ICAP_REG_SZ 0x108 +#define ICAP_REG_CR 0x10C +#define ICAP_REG_SR 0x110 +#define ICAP_REG_WFV 0x114 +#define ICAP_REG_RFO 0x118 +#define ICAP_REG_ASR 0x11C + +#define ICAP_STATUS_EOS 0x4 +#define ICAP_STATUS_DONE 0x1 + +/* + * Canned command sequence to obtain IDCODE of the FPGA + */ +static const u32 idcode_stream[] = { + /* dummy word */ + cpu_to_be32(0xffffffff), + /* sync word */ + cpu_to_be32(0xaa995566), + /* NOP word */ + cpu_to_be32(0x20000000), + /* NOP word */ + cpu_to_be32(0x20000000), + /* ID code */ + cpu_to_be32(0x28018001), + /* NOP word */ + cpu_to_be32(0x20000000), + /* NOP word */ + cpu_to_be32(0x20000000), +}; + +XRT_DEFINE_REGMAP_CONFIG(icap_regmap_config); + +struct icap { + struct xrt_device *xdev; + struct regmap *regmap; + struct mutex icap_lock; /* icap dev lock */
ok Reviwed-by: Tom Rix <trix@xxxxxxxxxx>
+ u32 idcode; +}; + +static int wait_for_done(const struct icap *icap) +{ + int i = 0; + int ret; + u32 w; + + for (i = 0; i < 10; i++) { + /* + * it requires few micro seconds for ICAP to process incoming data. + * Polling every 5us for 10 times would be good enough. + */ + udelay(5); + ret = regmap_read(icap->regmap, ICAP_REG_SR, &w); + if (ret) + return ret; + ICAP_INFO(icap, "XHWICAP_SR: %x", w); + if (w & (ICAP_STATUS_EOS | ICAP_STATUS_DONE)) + return 0; + } + + ICAP_ERR(icap, "bitstream download timeout"); + return -ETIMEDOUT; +} + +static int icap_write(const struct icap *icap, const u32 *word_buf, int size) +{ + u32 value = 0; + int ret; + int i; + + for (i = 0; i < size; i++) { + value = be32_to_cpu(word_buf[i]); + ret = regmap_write(icap->regmap, ICAP_REG_WF, value); + if (ret) + return ret; + } + + ret = regmap_write(icap->regmap, ICAP_REG_CR, 0x1); + if (ret) + return ret; + + for (i = 0; i < 20; i++) { + ret = regmap_read(icap->regmap, ICAP_REG_CR, &value); + if (ret) + return ret; + + if ((value & 0x1) == 0) + return 0; + ndelay(50); + } + + ICAP_ERR(icap, "writing %d dwords timeout", size); + return -EIO; +} + +static int bitstream_helper(struct icap *icap, const u32 *word_buffer, + u32 word_count) +{ + int wr_fifo_vacancy = 0; + u32 word_written = 0; + u32 remain_word; + int err = 0; + + WARN_ON(!mutex_is_locked(&icap->icap_lock)); + for (remain_word = word_count; remain_word > 0; + remain_word -= word_written, word_buffer += word_written) { + err = regmap_read(icap->regmap, ICAP_REG_WFV, &wr_fifo_vacancy); + if (err) { + ICAP_ERR(icap, "read wr_fifo_vacancy failed %d", err); + break; + } + if (wr_fifo_vacancy <= 0) { + ICAP_ERR(icap, "no vacancy: %d", wr_fifo_vacancy); + err = -EIO; + break; + } + word_written = (wr_fifo_vacancy < remain_word) ? + wr_fifo_vacancy : remain_word; + if (icap_write(icap, word_buffer, word_written) != 0) { + ICAP_ERR(icap, "write failed remain %d, written %d", + remain_word, word_written); + err = -EIO; + break; + } + } + + return err; +} + +static int icap_download(struct icap *icap, const char *buffer, + unsigned long length) +{ + u32 num_chars_read = XCLBIN_HWICAP_BITFILE_BUF_SZ; + u32 byte_read; + int err = 0; + + if (length % sizeof(u32)) { + ICAP_ERR(icap, "invalid bitstream length %ld", length); + return -EINVAL; + } + + mutex_lock(&icap->icap_lock); + for (byte_read = 0; byte_read < length; byte_read += num_chars_read) { + num_chars_read = length - byte_read; + if (num_chars_read > XCLBIN_HWICAP_BITFILE_BUF_SZ) + num_chars_read = XCLBIN_HWICAP_BITFILE_BUF_SZ; + + err = bitstream_helper(icap, (u32 *)buffer, num_chars_read / sizeof(u32)); + if (err) + goto failed; + buffer += num_chars_read; + } + + /* there is not any cleanup needs to be done if writing ICAP timeout. */ + err = wait_for_done(icap); + +failed: + mutex_unlock(&icap->icap_lock); + + return err; +} + +/* + * Discover the FPGA IDCODE using special sequence of canned commands + */ +static int icap_probe_chip(struct icap *icap) +{ + int err; + u32 val = 0; + + regmap_read(icap->regmap, ICAP_REG_SR, &val); + if (val != ICAP_STATUS_DONE) + return -ENODEV; + /* Read ICAP FIFO vacancy */ + regmap_read(icap->regmap, ICAP_REG_WFV, &val); + if (val < 8) + return -ENODEV; + err = icap_write(icap, idcode_stream, ARRAY_SIZE(idcode_stream)); + if (err) + return err; + err = wait_for_done(icap); + if (err) + return err; + + /* Tell config engine how many words to transfer to read FIFO */ + regmap_write(icap->regmap, ICAP_REG_SZ, 0x1); + /* Switch the ICAP to read mode */ + regmap_write(icap->regmap, ICAP_REG_CR, 0x2); + err = wait_for_done(icap); + if (err) + return err; + + /* Read IDCODE from Read FIFO */ + regmap_read(icap->regmap, ICAP_REG_RF, &icap->idcode); + return 0; +} + +static int +xrt_icap_leaf_call(struct xrt_device *xdev, u32 cmd, void *arg) +{ + struct xrt_icap_wr *wr_arg = arg; + struct icap *icap; + int ret = 0; + + icap = xrt_get_drvdata(xdev); + + switch (cmd) { + case XRT_XLEAF_EVENT: + /* Does not handle any event. */ + break; + case XRT_ICAP_WRITE: + ret = icap_download(icap, wr_arg->xiiw_bit_data, + wr_arg->xiiw_data_len); + break; + case XRT_ICAP_GET_IDCODE: + *(u32 *)arg = icap->idcode; + break; + default: + ICAP_ERR(icap, "unknown command %d", cmd); + return -EINVAL; + } + + return ret; +} + +static int xrt_icap_probe(struct xrt_device *xdev) +{ + void __iomem *base = NULL; + struct resource *res; + struct icap *icap; + int result = 0; + + icap = devm_kzalloc(&xdev->dev, sizeof(*icap), GFP_KERNEL); + if (!icap) + return -ENOMEM; + + icap->xdev = xdev; + xrt_set_drvdata(xdev, icap); + mutex_init(&icap->icap_lock); + + xrt_info(xdev, "probing"); + res = xrt_get_resource(xdev, IORESOURCE_MEM, 0); + if (!res) + return -EINVAL; + + base = devm_ioremap_resource(&xdev->dev, res); + if (IS_ERR(base)) + return PTR_ERR(base); + + icap->regmap = devm_regmap_init_mmio(&xdev->dev, base, &icap_regmap_config); + if (IS_ERR(icap->regmap)) { + ICAP_ERR(icap, "init mmio failed"); + return PTR_ERR(icap->regmap); + } + /* Disable ICAP interrupts */ + regmap_write(icap->regmap, ICAP_REG_GIER, 0); + + result = icap_probe_chip(icap); + if (result) + xrt_err(xdev, "Failed to probe FPGA"); + else + xrt_info(xdev, "Discovered FPGA IDCODE %x", icap->idcode); + return result; +} + +static struct xrt_dev_endpoints xrt_icap_endpoints[] = { + { + .xse_names = (struct xrt_dev_ep_names[]) { + { .ep_name = XRT_MD_NODE_FPGA_CONFIG }, + { NULL }, + }, + .xse_min_ep = 1, + }, + { 0 }, +}; + +static struct xrt_driver xrt_icap_driver = { + .driver = { + .name = XRT_ICAP, + }, + .subdev_id = XRT_SUBDEV_ICAP, + .endpoints = xrt_icap_endpoints, + .probe = xrt_icap_probe, + .leaf_call = xrt_icap_leaf_call, +}; + +XRT_LEAF_INIT_FINI_FUNC(icap);