diff options
| author | Mark Brown <[email protected]> | 2017-02-19 16:35:15 +0000 |
|---|---|---|
| committer | Mark Brown <[email protected]> | 2017-02-19 16:35:15 +0000 |
| commit | 389dcb9df652856294774f0ddc66a3c5bb5f1794 (patch) | |
| tree | 96e44a343596d314fc66d94618cbb9316776fa4e /drivers/fpga/altera-fpga2sdram.c | |
| parent | 69973b830859bc6529a7a0468ba0d80ee5117826 (diff) | |
| parent | 42e0ebdef53d91891939a475c6ef23970829ff99 (diff) | |
Merge tag 'asoc-fix-v4.10-rc3' into asoc-linus
ASoC: Fixes for v4.10
As well as the usual smattering of driver specific fixes collected since
the merge window this has one particularly important fix to the core for
handling of aux_devs which was broken during the merge window by some of
the componentization refactoring.
# gpg: Signature made Wed 11 Jan 2017 17:26:37 GMT
# gpg: using RSA key ADE668AA675718B59FE29FEA24D68B725D5487D0
# gpg: issuer "[email protected]"
# gpg: key 0D9EACE2CD7BEEBC: no public key for trusted key - skipped
# gpg: key 0D9EACE2CD7BEEBC marked as ultimately trusted
# gpg: key CCB0A420AF88CD16: no public key for trusted key - skipped
# gpg: key CCB0A420AF88CD16 marked as ultimately trusted
# gpg: key 162614E316005C11: no public key for trusted key - skipped
# gpg: key 162614E316005C11 marked as ultimately trusted
# gpg: key A730C53A5621E907: no public key for trusted key - skipped
# gpg: key A730C53A5621E907 marked as ultimately trusted
# gpg: key 276568D75C6153AD: no public key for trusted key - skipped
# gpg: key 276568D75C6153AD marked as ultimately trusted
# gpg: Good signature from "Mark Brown <[email protected]>" [ultimate]
# gpg: aka "Mark Brown <[email protected]>" [ultimate]
# gpg: aka "Mark Brown <[email protected]>" [ultimate]
# gpg: aka "Mark Brown <[email protected]>" [ultimate]
# gpg: aka "Mark Brown <[email protected]>" [ultimate]
# gpg: aka "Mark Brown <[email protected]>" [ultimate]
Diffstat (limited to 'drivers/fpga/altera-fpga2sdram.c')
| -rw-r--r-- | drivers/fpga/altera-fpga2sdram.c | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/drivers/fpga/altera-fpga2sdram.c b/drivers/fpga/altera-fpga2sdram.c new file mode 100644 index 000000000000..d4eeb74388da --- /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(sysmgr)) { + 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 <[email protected]>"); +MODULE_LICENSE("GPL v2"); |