| From d4cd4955c34d18b9849d52ddfe6ca83f9f04e5a5 Mon Sep 17 00:00:00 2001 |
| From: Anatolij Gustschin <agust@denx.de> |
| Date: Thu, 23 Mar 2017 19:34:26 -0500 |
| Subject: [PATCH 055/103] fpga manager: Add Xilinx slave serial SPI driver |
| |
| The driver loads FPGA firmware over SPI, using the "slave serial" |
| configuration interface on Xilinx FPGAs. |
| |
| Signed-off-by: Anatolij Gustschin <agust@denx.de> |
| Acked-by: Michal Simek <michal.simek@xilinx.com> |
| Reviewed-by: Moritz Fischer <mdf@kernel.org> |
| Acked-by: Alan Tull <atull@kernel.org> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| drivers/fpga/Kconfig | 7 + |
| drivers/fpga/Makefile | 1 |
| drivers/fpga/xilinx-spi.c | 198 ++++++++++++++++++++++++++++++++++++++++++++++ |
| 3 files changed, 206 insertions(+) |
| create mode 100644 drivers/fpga/xilinx-spi.c |
| |
| --- a/drivers/fpga/Kconfig |
| +++ b/drivers/fpga/Kconfig |
| @@ -46,6 +46,13 @@ config FPGA_MGR_TS73XX |
| FPGA manager driver support for the Altera Cyclone II FPGA |
| present on the TS-73xx SBC boards. |
| |
| +config FPGA_MGR_XILINX_SPI |
| + tristate "Xilinx Configuration over Slave Serial (SPI)" |
| + depends on SPI |
| + help |
| + FPGA manager driver support for Xilinx FPGA configuration |
| + over slave serial interface. |
| + |
| config FPGA_MGR_ZYNQ_FPGA |
| tristate "Xilinx Zynq FPGA" |
| depends on ARCH_ZYNQ || COMPILE_TEST |
| --- a/drivers/fpga/Makefile |
| +++ b/drivers/fpga/Makefile |
| @@ -10,6 +10,7 @@ obj-$(CONFIG_FPGA_MGR_ICE40_SPI) += ice4 |
| obj-$(CONFIG_FPGA_MGR_SOCFPGA) += socfpga.o |
| obj-$(CONFIG_FPGA_MGR_SOCFPGA_A10) += socfpga-a10.o |
| obj-$(CONFIG_FPGA_MGR_TS73XX) += ts73xx-fpga.o |
| +obj-$(CONFIG_FPGA_MGR_XILINX_SPI) += xilinx-spi.o |
| obj-$(CONFIG_FPGA_MGR_ZYNQ_FPGA) += zynq-fpga.o |
| |
| # FPGA Bridge Drivers |
| --- /dev/null |
| +++ b/drivers/fpga/xilinx-spi.c |
| @@ -0,0 +1,198 @@ |
| +/* |
| + * Xilinx Spartan6 Slave Serial SPI Driver |
| + * |
| + * Copyright (C) 2017 DENX Software Engineering |
| + * |
| + * Anatolij Gustschin <agust@denx.de> |
| + * |
| + * This program is free software; you can redistribute it and/or modify it |
| + * under the terms and conditions of the GNU General Public License, |
| + * version 2, as published by the Free Software Foundation. |
| + * |
| + * Manage Xilinx FPGA firmware that is loaded over SPI using |
| + * the slave serial configuration interface. |
| + */ |
| + |
| +#include <linux/delay.h> |
| +#include <linux/device.h> |
| +#include <linux/fpga/fpga-mgr.h> |
| +#include <linux/gpio/consumer.h> |
| +#include <linux/module.h> |
| +#include <linux/mod_devicetable.h> |
| +#include <linux/of.h> |
| +#include <linux/spi/spi.h> |
| +#include <linux/sizes.h> |
| + |
| +struct xilinx_spi_conf { |
| + struct spi_device *spi; |
| + struct gpio_desc *prog_b; |
| + struct gpio_desc *done; |
| +}; |
| + |
| +static enum fpga_mgr_states xilinx_spi_state(struct fpga_manager *mgr) |
| +{ |
| + struct xilinx_spi_conf *conf = mgr->priv; |
| + |
| + if (!gpiod_get_value(conf->done)) |
| + return FPGA_MGR_STATE_RESET; |
| + |
| + return FPGA_MGR_STATE_UNKNOWN; |
| +} |
| + |
| +static int xilinx_spi_write_init(struct fpga_manager *mgr, |
| + struct fpga_image_info *info, |
| + const char *buf, size_t count) |
| +{ |
| + struct xilinx_spi_conf *conf = mgr->priv; |
| + const size_t prog_latency_7500us = 7500; |
| + const size_t prog_pulse_1us = 1; |
| + |
| + if (info->flags & FPGA_MGR_PARTIAL_RECONFIG) { |
| + dev_err(&mgr->dev, "Partial reconfiguration not supported.\n"); |
| + return -EINVAL; |
| + } |
| + |
| + gpiod_set_value(conf->prog_b, 1); |
| + |
| + udelay(prog_pulse_1us); /* min is 500 ns */ |
| + |
| + gpiod_set_value(conf->prog_b, 0); |
| + |
| + if (gpiod_get_value(conf->done)) { |
| + dev_err(&mgr->dev, "Unexpected DONE pin state...\n"); |
| + return -EIO; |
| + } |
| + |
| + /* program latency */ |
| + usleep_range(prog_latency_7500us, prog_latency_7500us + 100); |
| + return 0; |
| +} |
| + |
| +static int xilinx_spi_write(struct fpga_manager *mgr, const char *buf, |
| + size_t count) |
| +{ |
| + struct xilinx_spi_conf *conf = mgr->priv; |
| + const char *fw_data = buf; |
| + const char *fw_data_end = fw_data + count; |
| + |
| + while (fw_data < fw_data_end) { |
| + size_t remaining, stride; |
| + int ret; |
| + |
| + remaining = fw_data_end - fw_data; |
| + stride = min_t(size_t, remaining, SZ_4K); |
| + |
| + ret = spi_write(conf->spi, fw_data, stride); |
| + if (ret) { |
| + dev_err(&mgr->dev, "SPI error in firmware write: %d\n", |
| + ret); |
| + return ret; |
| + } |
| + fw_data += stride; |
| + } |
| + |
| + return 0; |
| +} |
| + |
| +static int xilinx_spi_apply_cclk_cycles(struct xilinx_spi_conf *conf) |
| +{ |
| + struct spi_device *spi = conf->spi; |
| + const u8 din_data[1] = { 0xff }; |
| + int ret; |
| + |
| + ret = spi_write(conf->spi, din_data, sizeof(din_data)); |
| + if (ret) |
| + dev_err(&spi->dev, "applying CCLK cycles failed: %d\n", ret); |
| + |
| + return ret; |
| +} |
| + |
| +static int xilinx_spi_write_complete(struct fpga_manager *mgr, |
| + struct fpga_image_info *info) |
| +{ |
| + struct xilinx_spi_conf *conf = mgr->priv; |
| + unsigned long timeout; |
| + int ret; |
| + |
| + if (gpiod_get_value(conf->done)) |
| + return xilinx_spi_apply_cclk_cycles(conf); |
| + |
| + timeout = jiffies + usecs_to_jiffies(info->config_complete_timeout_us); |
| + |
| + while (time_before(jiffies, timeout)) { |
| + |
| + ret = xilinx_spi_apply_cclk_cycles(conf); |
| + if (ret) |
| + return ret; |
| + |
| + if (gpiod_get_value(conf->done)) |
| + return xilinx_spi_apply_cclk_cycles(conf); |
| + } |
| + |
| + dev_err(&mgr->dev, "Timeout after config data transfer.\n"); |
| + return -ETIMEDOUT; |
| +} |
| + |
| +static const struct fpga_manager_ops xilinx_spi_ops = { |
| + .state = xilinx_spi_state, |
| + .write_init = xilinx_spi_write_init, |
| + .write = xilinx_spi_write, |
| + .write_complete = xilinx_spi_write_complete, |
| +}; |
| + |
| +static int xilinx_spi_probe(struct spi_device *spi) |
| +{ |
| + struct xilinx_spi_conf *conf; |
| + |
| + conf = devm_kzalloc(&spi->dev, sizeof(*conf), GFP_KERNEL); |
| + if (!conf) |
| + return -ENOMEM; |
| + |
| + conf->spi = spi; |
| + |
| + /* PROGRAM_B is active low */ |
| + conf->prog_b = devm_gpiod_get(&spi->dev, "prog_b", GPIOD_OUT_LOW); |
| + if (IS_ERR(conf->prog_b)) { |
| + dev_err(&spi->dev, "Failed to get PROGRAM_B gpio: %ld\n", |
| + PTR_ERR(conf->prog_b)); |
| + return PTR_ERR(conf->prog_b); |
| + } |
| + |
| + conf->done = devm_gpiod_get(&spi->dev, "done", GPIOD_IN); |
| + if (IS_ERR(conf->done)) { |
| + dev_err(&spi->dev, "Failed to get DONE gpio: %ld\n", |
| + PTR_ERR(conf->done)); |
| + return PTR_ERR(conf->done); |
| + } |
| + |
| + return fpga_mgr_register(&spi->dev, "Xilinx Slave Serial FPGA Manager", |
| + &xilinx_spi_ops, conf); |
| +} |
| + |
| +static int xilinx_spi_remove(struct spi_device *spi) |
| +{ |
| + fpga_mgr_unregister(&spi->dev); |
| + |
| + return 0; |
| +} |
| + |
| +static const struct of_device_id xlnx_spi_of_match[] = { |
| + { .compatible = "xlnx,fpga-slave-serial", }, |
| + {} |
| +}; |
| +MODULE_DEVICE_TABLE(of, xlnx_spi_of_match); |
| + |
| +static struct spi_driver xilinx_slave_spi_driver = { |
| + .driver = { |
| + .name = "xlnx-slave-spi", |
| + .of_match_table = of_match_ptr(xlnx_spi_of_match), |
| + }, |
| + .probe = xilinx_spi_probe, |
| + .remove = xilinx_spi_remove, |
| +}; |
| + |
| +module_spi_driver(xilinx_slave_spi_driver) |
| + |
| +MODULE_LICENSE("GPL v2"); |
| +MODULE_AUTHOR("Anatolij Gustschin <agust@denx.de>"); |
| +MODULE_DESCRIPTION("Load Xilinx FPGA firmware over SPI"); |