Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754011AbcLKWiL (ORCPT ); Sun, 11 Dec 2016 17:38:11 -0500 Received: from mail-qk0-f174.google.com ([209.85.220.174]:36577 "EHLO mail-qk0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753896AbcLKWiJ (ORCPT ); Sun, 11 Dec 2016 17:38:09 -0500 MIME-Version: 1.0 In-Reply-To: <20161211221750.27743-3-f.fainelli@gmail.com> References: <20161211221750.27743-1-f.fainelli@gmail.com> <20161211221750.27743-3-f.fainelli@gmail.com> From: Moritz Fischer Date: Sun, 11 Dec 2016 14:38:07 -0800 Message-ID: Subject: Re: [PATCH 2/2] FPGA: Add TS-7300 FPGA manager To: Florian Fainelli Cc: Linux Kernel Mailing List , linux-arm-kernel , Alan Tull , Russell King , rmallon@gmail.com, H Hartley Sweeten , linux-fpga@vger.kernel.org Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7286 Lines: 236 Hi Florian, can you Cc: linxu-fpga@vger.kernel.org for your next round? On Sun, Dec 11, 2016 at 2:17 PM, Florian Fainelli wrote: > Add support for loading bitstreams on the Altera Cyclone II FPGA > populated on the TS-7300 board. This is done through the configuration > and data registers offered through a memory interface between the EP93xx > SoC and the FPGA. > > Signed-off-by: Florian Fainelli > --- > drivers/fpga/Kconfig | 7 ++ > drivers/fpga/Makefile | 1 + > drivers/fpga/ts73xx-fpga.c | 165 +++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 173 insertions(+) > create mode 100644 drivers/fpga/ts73xx-fpga.c > > diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig > index cd84934774cc..109625707ef0 100644 > --- a/drivers/fpga/Kconfig > +++ b/drivers/fpga/Kconfig > @@ -26,6 +26,13 @@ config FPGA_MGR_ZYNQ_FPGA > help > FPGA manager driver support for Xilinx Zynq FPGAs. > > +config FPGA_MGR_TS73XX > + tristate "Technologic Systems TS-73xx SBC FPGA Manager" > + depends on ARCH_EP93XX && MACH_TS72XX > + help > + FPGA manager driver support for the Altera Cyclone II FPGA > + present on the TS-73xx SBC boards. > + > endif # FPGA > > endmenu > diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile > index 8d83fc6b1613..5d51265cc1b4 100644 > --- a/drivers/fpga/Makefile > +++ b/drivers/fpga/Makefile > @@ -8,3 +8,4 @@ obj-$(CONFIG_FPGA) += fpga-mgr.o > # FPGA Manager Drivers > obj-$(CONFIG_FPGA_MGR_SOCFPGA) += socfpga.o > obj-$(CONFIG_FPGA_MGR_ZYNQ_FPGA) += zynq-fpga.o > +obj-$(CONFIG_FPGA_MGR_TS73XX) += ts73xx-fpga.o > diff --git a/drivers/fpga/ts73xx-fpga.c b/drivers/fpga/ts73xx-fpga.c > new file mode 100644 > index 000000000000..2b3d5d668dfc > --- /dev/null > +++ b/drivers/fpga/ts73xx-fpga.c > @@ -0,0 +1,165 @@ > +/* > + * Technologic Systems TS-73xx SBC FPGA loader > + * > + * Copyright (C) 2016 Florian Fainelli > + * > + * FPGA Manager Driver for the on-board Altera Cyclone II FPGA found on > + * TS-7300, heavily based on load_fpga.c in their vendor tree. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; version 2 of the License. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#define TS73XX_FPGA_DATA_REG 0 > +#define TS73XX_FPGA_CONFIG_REG 1 > + > +struct ts73xx_fpga_priv { > + void __iomem *io_base; > + struct device *dev; > +}; > + > +static enum fpga_mgr_states ts73xx_fpga_state(struct fpga_manager *mgr) > +{ > + return FPGA_MGR_STATE_UNKNOWN; > +} > + > +static int ts73xx_fpga_write_init(struct fpga_manager *mgr, u32 flags, > + const char *buf, size_t count) > +{ > + struct ts73xx_fpga_priv *priv = mgr->priv; > + > + /* Reset the FPGA */ > + writeb(0, priv->io_base + TS73XX_FPGA_CONFIG_REG); > + udelay(30); > + writeb(0x2, priv->io_base + TS73XX_FPGA_CONFIG_REG); > + udelay(80); > + > + return 0; > +} > + > +static inline int ts73xx_fpga_can_write(struct ts73xx_fpga_priv *priv) > +{ > + unsigned int timeout = 1000; > + u8 reg; > + > + while (timeout--) { > + reg = readb(priv->io_base + TS73XX_FPGA_CONFIG_REG); > + if (!(reg & 0x1)) > + return 0; > + cpu_relax(); > + } You can use readb_poll_timeout() for this I think. > + > + return -ETIMEDOUT; > +} > + > +static int ts73xx_fpga_write(struct fpga_manager *mgr, const char *buf, > + size_t count) > +{ > + struct ts73xx_fpga_priv *priv = mgr->priv; > + size_t i = 0; > + int ret; > + u8 reg; > + > + while (count--) { > + ret = ts73xx_fpga_can_write(priv); > + if (ret < 0) > + return ret; > + > + writeb(buf[i], priv->io_base + TS73XX_FPGA_DATA_REG); > + i++; > + } > + > + usleep_range(1000, 2000); > + reg = readb(priv->io_base + TS73XX_FPGA_CONFIG_REG); > + reg |= 0x8; What's happening here? > + writeb(reg, priv->io_base + TS73XX_FPGA_CONFIG_REG); > + usleep_range(1000, 2000); > + > + reg = readb(priv->io_base + TS73XX_FPGA_CONFIG_REG); > + reg &= ~0x8; and here? Can we have a named constant for these, or a comment to explain what happens? > + writeb(reg, priv->io_base + TS73XX_FPGA_CONFIG_REG); > + > + return 0; > +} > + > +static int ts73xx_fpga_write_complete(struct fpga_manager *mgr, u32 flags) > +{ > + struct ts73xx_fpga_priv *priv = mgr->priv; > + u8 reg; > + > + reg = readb(priv->io_base + TS73XX_FPGA_CONFIG_REG); > + if ((reg & 0x4) != 0x4) Named constants, please > + return -ETIMEDOUT; > + > + return 0; > +} > + > +static const struct fpga_manager_ops ts73xx_fpga_ops = { > + .state = ts73xx_fpga_state, > + .write_init = ts73xx_fpga_write_init, > + .write = ts73xx_fpga_write, > + .write_complete = ts73xx_fpga_write_complete, > +}; > + > +static int ts73xx_fpga_probe(struct platform_device *pdev) > +{ > + struct device *kdev = &pdev->dev; > + struct ts73xx_fpga_priv *priv; > + struct fpga_manager *mgr; > + struct resource *res; > + int err; > + > + priv = devm_kzalloc(kdev, sizeof(*priv), GFP_KERNEL); > + if (!priv) > + return -ENOMEM; > + > + priv->dev = kdev; > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + priv->io_base = devm_ioremap_resource(kdev, res); > + if (IS_ERR(priv->io_base)) > + return PTR_ERR(priv->io_base); Maybe an error message here? > + > + err = fpga_mgr_register(kdev, "TS-73xx FPGA Manager", > + &ts73xx_fpga_ops, priv); > + if (err) { > + dev_err(kdev, "failed to register FPGA manager\n"); > + return err; > + } > + > + return err; > +} > + > +static int ts73xx_fpga_remove(struct platform_device *pdev) > +{ > + fpga_mgr_unregister(&pdev->dev); > + > + return 0; > +} > + > +static struct platform_driver ts73xx_fpga_driver = { > + .driver = { > + .name = "ts73xx-fpga-mgr", > + }, > + .probe = ts73xx_fpga_probe, > + .remove = ts73xx_fpga_remove, > +}; > +module_platform_driver(ts73xx_fpga_driver); > + > +MODULE_AUTHOR("Florian Fainelli "); > +MODULE_DESCRIPTION("TS-73xx FPGA Manager driver"); > +MODULE_LICENSE("GPL v2"); > -- > 2.9.3 > Thanks, Moritz