diff options
| -rw-r--r-- | drivers/fpga/Kconfig | 7 | ||||
| -rw-r--r-- | drivers/fpga/Makefile | 1 | ||||
| -rw-r--r-- | drivers/fpga/altera-fpga2sdram.c | 180 | ||||
| -rw-r--r-- | drivers/fpga/altera-hps2fpga.c | 222 |
4 files changed, 410 insertions, 0 deletions
diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig index e0e1257e17e2..5605ad6a4e97 100644 --- a/drivers/fpga/Kconfig +++ b/drivers/fpga/Kconfig @@ -40,6 +40,13 @@ config FPGA_BRIDGE Say Y here if you want to support bridges connected between host processors and FPGAs or between FPGAs. +config SOCFPGA_FPGA_BRIDGE + tristate "Altera SoCFPGA FPGA Bridges" + depends on ARCH_SOCFPGA && FPGA_BRIDGE + help + Say Y to enable drivers for FPGA bridges for Altera SOCFPGA + devices. + endif # FPGA endmenu diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile index 8d746c342533..e658436f2c75 100644 --- a/drivers/fpga/Makefile +++ b/drivers/fpga/Makefile @@ -11,6 +11,7 @@ obj-$(CONFIG_FPGA_MGR_ZYNQ_FPGA) += zynq-fpga.o # FPGA Bridge Drivers obj-$(CONFIG_FPGA_BRIDGE) += fpga-bridge.o +obj-$(CONFIG_SOCFPGA_FPGA_BRIDGE) += altera-hps2fpga.o altera-fpga2sdram.o # High Level Interfaces obj-$(CONFIG_FPGA_REGION) += fpga-region.o diff --git a/drivers/fpga/altera-fpga2sdram.c b/drivers/fpga/altera-fpga2sdram.c new file mode 100644 index 000000000000..7ab358ed6c76 --- /dev/null +++ b/drivers/fpga/altera-fpga2sdram.c @@ -0,0 +1,180 @@ +/* + * FPGA to SDRAM Bridge Driver for Altera SoCFPGA Devices + * + * Copyright (C) 2013-2016 Altera Corporation, All Rights Reserved. + * + * 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. + * + * This program is distributed in the hope 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. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see <http://www.gnu.org/licenses/>. + */ + +/* + * This driver manages a bridge between an FPGA and the SDRAM used by the ARM + * host processor system (HPS). + * + * The bridge contains 4 read ports, 4 write ports, and 6 command ports. + * Reconfiguring these ports requires that no SDRAM transactions occur during + * reconfiguration. The code reconfiguring the ports cannot run out of SDRAM + * nor can the FPGA access the SDRAM during reconfiguration. This driver does + * not support reconfiguring the ports. The ports are configured by code + * running out of on chip ram before Linux is started and the configuration + * is passed in a handoff register in the system manager. + * + * This driver supports enabling and disabling of the configured ports, which + * allows for safe reprogramming of the FPGA, assuming that the new FPGA image + * uses the same port configuration. Bridges must be disabled before + * reprogramming the FPGA and re-enabled after the FPGA has been programmed. + */ + +#include <linux/fpga/fpga-bridge.h> +#include <linux/kernel.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of_platform.h> +#include <linux/regmap.h> + +#define ALT_SDR_CTL_FPGAPORTRST_OFST 0x80 +#define ALT_SDR_CTL_FPGAPORTRST_PORTRSTN_MSK 0x00003fff +#define ALT_SDR_CTL_FPGAPORTRST_RD_SHIFT 0 +#define ALT_SDR_CTL_FPGAPORTRST_WR_SHIFT 4 +#define ALT_SDR_CTL_FPGAPORTRST_CTRL_SHIFT 8 + +/* + * From the Cyclone V HPS Memory Map document: + * These registers are used to store handoff information between the + * preloader and the OS. These 8 registers can be used to store any + * information. The contents of these registers have no impact on + * the state of the HPS hardware. + */ +#define SYSMGR_ISWGRP_HANDOFF3 (0x8C) + +#define F2S_BRIDGE_NAME "fpga2sdram" + +struct alt_fpga2sdram_data { + struct device *dev; + struct regmap *sdrctl; + int mask; +}; + +static int alt_fpga2sdram_enable_show(struct fpga_bridge *bridge) +{ + struct alt_fpga2sdram_data *priv = bridge->priv; + int value; + + regmap_read(priv->sdrctl, ALT_SDR_CTL_FPGAPORTRST_OFST, &value); + + return (value & priv->mask) == priv->mask; +} + +static inline int _alt_fpga2sdram_enable_set(struct alt_fpga2sdram_data *priv, + bool enable) +{ + return regmap_update_bits(priv->sdrctl, ALT_SDR_CTL_FPGAPORTRST_OFST, + priv->mask, enable ? priv->mask : 0); +} + +static int alt_fpga2sdram_enable_set(struct fpga_bridge *bridge, bool enable) +{ + return _alt_fpga2sdram_enable_set(bridge->priv, enable); +} + +struct prop_map { + char *prop_name; + u32 *prop_value; + u32 prop_max; +}; + +static const struct fpga_bridge_ops altera_fpga2sdram_br_ops = { + .enable_set = alt_fpga2sdram_enable_set, + .enable_show = alt_fpga2sdram_enable_show, +}; + +static const struct of_device_id altera_fpga_of_match[] = { + { .compatible = "altr,socfpga-fpga2sdram-bridge" }, + {}, +}; + +static int alt_fpga_bridge_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct alt_fpga2sdram_data *priv; + u32 enable; + struct regmap *sysmgr; + int ret = 0; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->dev = dev; + + priv->sdrctl = syscon_regmap_lookup_by_compatible("altr,sdr-ctl"); + if (IS_ERR(priv->sdrctl)) { + dev_err(dev, "regmap for altr,sdr-ctl lookup failed.\n"); + return PTR_ERR(priv->sdrctl); + } + + sysmgr = syscon_regmap_lookup_by_compatible("altr,sys-mgr"); + if (IS_ERR(priv->sdrctl)) { + dev_err(dev, "regmap for altr,sys-mgr lookup failed.\n"); + return PTR_ERR(sysmgr); + } + + /* Get f2s bridge configuration saved in handoff register */ + regmap_read(sysmgr, SYSMGR_ISWGRP_HANDOFF3, &priv->mask); + + ret = fpga_bridge_register(dev, F2S_BRIDGE_NAME, + &altera_fpga2sdram_br_ops, priv); + if (ret) + return ret; + + dev_info(dev, "driver initialized with handoff %08x\n", priv->mask); + + if (!of_property_read_u32(dev->of_node, "bridge-enable", &enable)) { + if (enable > 1) { + dev_warn(dev, "invalid bridge-enable %u > 1\n", enable); + } else { + dev_info(dev, "%s bridge\n", + (enable ? "enabling" : "disabling")); + ret = _alt_fpga2sdram_enable_set(priv, enable); + if (ret) { + fpga_bridge_unregister(&pdev->dev); + return ret; + } + } + } + + return ret; +} + +static int alt_fpga_bridge_remove(struct platform_device *pdev) +{ + fpga_bridge_unregister(&pdev->dev); + + return 0; +} + +MODULE_DEVICE_TABLE(of, altera_fpga_of_match); + +static struct platform_driver altera_fpga_driver = { + .probe = alt_fpga_bridge_probe, + .remove = alt_fpga_bridge_remove, + .driver = { + .name = "altera_fpga2sdram_bridge", + .of_match_table = of_match_ptr(altera_fpga_of_match), + }, +}; + +module_platform_driver(altera_fpga_driver); + +MODULE_DESCRIPTION("Altera SoCFPGA FPGA to SDRAM Bridge"); +MODULE_AUTHOR("Alan Tull <atull@opensource.altera.com>"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/fpga/altera-hps2fpga.c b/drivers/fpga/altera-hps2fpga.c new file mode 100644 index 000000000000..4b354c79be31 --- /dev/null +++ b/drivers/fpga/altera-hps2fpga.c @@ -0,0 +1,222 @@ +/* + * FPGA to/from HPS Bridge Driver for Altera SoCFPGA Devices + * + * Copyright (C) 2013-2016 Altera Corporation, All Rights Reserved. + * + * Includes this patch from the mailing list: + * fpga: altera-hps2fpga: fix HPS2FPGA bridge visibility to L3 masters + * Signed-off-by: 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. + * + * This program is distributed in the hope 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. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see <http://www.gnu.org/licenses/>. + */ + +/* + * This driver manages bridges on a Altera SOCFPGA between the ARM host + * processor system (HPS) and the embedded FPGA. + * + * This driver supports enabling and disabling of the configured ports, which + * allows for safe reprogramming of the FPGA, assuming that the new FPGA image + * uses the same port configuration. Bridges must be disabled before + * reprogramming the FPGA and re-enabled after the FPGA has been programmed. + */ + +#include <linux/clk.h> +#include <linux/fpga/fpga-bridge.h> +#include <linux/kernel.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of_platform.h> +#include <linux/regmap.h> +#include <linux/reset.h> +#include <linux/spinlock.h> + +#define ALT_L3_REMAP_OFST 0x0 +#define ALT_L3_REMAP_MPUZERO_MSK 0x00000001 +#define ALT_L3_REMAP_H2F_MSK 0x00000008 +#define ALT_L3_REMAP_LWH2F_MSK 0x00000010 + +#define HPS2FPGA_BRIDGE_NAME "hps2fpga" +#define LWHPS2FPGA_BRIDGE_NAME "lwhps2fpga" +#define FPGA2HPS_BRIDGE_NAME "fpga2hps" + +struct altera_hps2fpga_data { + const char *name; + struct reset_control *bridge_reset; + struct regmap *l3reg; + unsigned int remap_mask; + struct clk *clk; +}; + +static int alt_hps2fpga_enable_show(struct fpga_bridge *bridge) +{ + struct altera_hps2fpga_data *priv = bridge->priv; + + return reset_control_status(priv->bridge_reset); +} + +/* The L3 REMAP register is write only, so keep a cached value. */ +static unsigned int l3_remap_shadow; +static spinlock_t l3_remap_lock; + +static int _alt_hps2fpga_enable_set(struct altera_hps2fpga_data *priv, + bool enable) +{ + unsigned long flags; + int ret; + + /* bring bridge out of reset */ + if (enable) + ret = reset_control_deassert(priv->bridge_reset); + else + ret = reset_control_assert(priv->bridge_reset); + if (ret) + return ret; + + /* Allow bridge to be visible to L3 masters or not */ + if (priv->remap_mask) { + spin_lock_irqsave(&l3_remap_lock, flags); + l3_remap_shadow |= ALT_L3_REMAP_MPUZERO_MSK; + + if (enable) + l3_remap_shadow |= priv->remap_mask; + else + l3_remap_shadow &= ~priv->remap_mask; + + ret = regmap_write(priv->l3reg, ALT_L3_REMAP_OFST, + l3_remap_shadow); + spin_unlock_irqrestore(&l3_remap_lock, flags); + } + + return ret; +} + +static int alt_hps2fpga_enable_set(struct fpga_bridge *bridge, bool enable) +{ + return _alt_hps2fpga_enable_set(bridge->priv, enable); +} + +static const struct fpga_bridge_ops altera_hps2fpga_br_ops = { + .enable_set = alt_hps2fpga_enable_set, + .enable_show = alt_hps2fpga_enable_show, +}; + +static struct altera_hps2fpga_data hps2fpga_data = { + .name = HPS2FPGA_BRIDGE_NAME, + .remap_mask = ALT_L3_REMAP_H2F_MSK, +}; + +static struct altera_hps2fpga_data lwhps2fpga_data = { + .name = LWHPS2FPGA_BRIDGE_NAME, + .remap_mask = ALT_L3_REMAP_LWH2F_MSK, +}; + +static struct altera_hps2fpga_data fpga2hps_data = { + .name = FPGA2HPS_BRIDGE_NAME, +}; + +static const struct of_device_id altera_fpga_of_match[] = { + { .compatible = "altr,socfpga-hps2fpga-bridge", + .data = &hps2fpga_data }, + { .compatible = "altr,socfpga-lwhps2fpga-bridge", + .data = &lwhps2fpga_data }, + { .compatible = "altr,socfpga-fpga2hps-bridge", + .data = &fpga2hps_data }, + {}, +}; + +static int alt_fpga_bridge_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct altera_hps2fpga_data *priv; + const struct of_device_id *of_id; + u32 enable; + int ret; + + of_id = of_match_device(altera_fpga_of_match, dev); + priv = (struct altera_hps2fpga_data *)of_id->data; + + priv->bridge_reset = of_reset_control_get_by_index(dev->of_node, 0); + if (IS_ERR(priv->bridge_reset)) { + dev_err(dev, "Could not get %s reset control\n", priv->name); + return PTR_ERR(priv->bridge_reset); + } + + if (priv->remap_mask) { + priv->l3reg = syscon_regmap_lookup_by_compatible("altr,l3regs"); + if (IS_ERR(priv->l3reg)) { + dev_err(dev, "regmap for altr,l3regs lookup failed\n"); + return PTR_ERR(priv->l3reg); + } + } + + priv->clk = devm_clk_get(dev, NULL); + if (IS_ERR(priv->clk)) { + dev_err(dev, "no clock specified\n"); + return PTR_ERR(priv->clk); + } + + ret = clk_prepare_enable(priv->clk); + if (ret) { + dev_err(dev, "could not enable clock\n"); + return -EBUSY; + } + + spin_lock_init(&l3_remap_lock); + + if (!of_property_read_u32(dev->of_node, "bridge-enable", &enable)) { + if (enable > 1) { + dev_warn(dev, "invalid bridge-enable %u > 1\n", enable); + } else { + dev_info(dev, "%s bridge\n", + (enable ? "enabling" : "disabling")); + + ret = _alt_hps2fpga_enable_set(priv, enable); + if (ret) { + fpga_bridge_unregister(&pdev->dev); + return ret; + } + } + } + + return fpga_bridge_register(dev, priv->name, &altera_hps2fpga_br_ops, + priv); +} + +static int alt_fpga_bridge_remove(struct platform_device *pdev) +{ + struct fpga_bridge *bridge = platform_get_drvdata(pdev); + struct altera_hps2fpga_data *priv = bridge->priv; + + fpga_bridge_unregister(&pdev->dev); + + clk_disable_unprepare(priv->clk); + + return 0; +} + +MODULE_DEVICE_TABLE(of, altera_fpga_of_match); + +static struct platform_driver alt_fpga_bridge_driver = { + .probe = alt_fpga_bridge_probe, + .remove = alt_fpga_bridge_remove, + .driver = { + .name = "altera_hps2fpga_bridge", + .of_match_table = of_match_ptr(altera_fpga_of_match), + }, +}; + +module_platform_driver(alt_fpga_bridge_driver); + +MODULE_DESCRIPTION("Altera SoCFPGA HPS to FPGA Bridge"); +MODULE_AUTHOR("Alan Tull <atull@opensource.altera.com>"); +MODULE_LICENSE("GPL v2"); |