From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752803AbdCPO74 (ORCPT ); Thu, 16 Mar 2017 10:59:56 -0400 Received: from mail.kernel.org ([198.145.29.136]:47896 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753948AbdCPO7J (ORCPT ); Thu, 16 Mar 2017 10:59:09 -0400 MIME-Version: 1.0 In-Reply-To: <1488300022-30150-3-git-send-email-agust@denx.de> References: <1488300022-30150-1-git-send-email-agust@denx.de> <1488300022-30150-3-git-send-email-agust@denx.de> From: Moritz Fischer Date: Thu, 16 Mar 2017 07:58:17 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v4 2/2] fpga manager: Add Xilinx slave serial SPI driver To: Anatolij Gustschin Cc: linux-fpga@vger.kernel.org, Linux Kernel Mailing List , Devicetree List , Alan Tull , Rob Herring , Mark Rutland Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Feb 28, 2017 at 8:40 AM, Anatolij Gustschin wrote: > The driver loads FPGA firmware over SPI, using the "slave serial" > configuration interface on Xilinx FPGAs. > > Signed-off-by: Anatolij Gustschin Reviewed-by: Moritz Fischer > --- > This patch requires patch https://lkml.org/lkml/2017/2/15/667 > for building > > Changes in v4: > > - increase program latency up to 7.5ms for other Xilinx FPGAs > - continue to apply CCLK cycles until specified timeout elapses (to > cover more possible configuration DONE scenarios) > - apply 8 CCLK cycles afer DONE signal > - rebased to apply on top of Kconfig/Makefile changes by queued > fpga manager patches > > Changes in v3: > > - use named constant for udelay()/usleep_range() arguments > - drop not needed .owner init > - correct module licence (GPL v2) > - fix build warning with newer gcc (in min() macro) > > Changes in v2: > > - rebased on v4.10 > > 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 > > diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig > index dee470f..c81cb7d 100644 > --- 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 > diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile > index a5ee3ff..c6f5d74 100644 > --- a/drivers/fpga/Makefile > +++ b/drivers/fpga/Makefile > @@ -10,6 +10,7 @@ obj-$(CONFIG_FPGA_MGR_ICE40_SPI) += ice40-spi.o > obj-$(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 > diff --git a/drivers/fpga/xilinx-spi.c b/drivers/fpga/xilinx-spi.c > new file mode 100644 > index 0000000..9b62a4c > --- /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 > + * > + * 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 > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +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 "); > +MODULE_DESCRIPTION("Load Xilinx FPGA firmware over SPI"); > -- > 2.7.4 >