fpga manager: Add Altera CvP driver

Add FPGA manager driver for loading Arria-V/Cyclone-V/Stratix-V
and Arria-10 FPGAs via CvP.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Alan Tull <atull@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 500 insertions, 0 deletions

diff --git a/drivers/fpga/altera-cvp.c b/drivers/fpga/altera-cvp.c
new file mode 100644
index 000000000000..08629ee69d11
--- /dev/null
+++ b/drivers/fpga/altera-cvp.c
@@ -0,0 +1,500 @@
+/*
+ * FPGA Manager Driver for Altera Arria/Cyclone/Stratix CvP
+ *
+ * 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 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.
+ *
+ * Manage Altera FPGA firmware using PCIe CvP.
+ * Firmware must be in binary "rbf" format.
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/sizes.h>
+
+#define CVP_BAR         0       /* BAR used for data transfer in memory mode */
+#define CVP_DUMMY_WR    244     /* dummy writes to clear CvP state machine */
+#define TIMEOUT_US      2000    /* CVP STATUS timeout for USERMODE polling */
+
+/* Vendor Specific Extended Capability Registers */
+#define VSE_PCIE_EXT_CAP_ID             0x200
+#define VSE_PCIE_EXT_CAP_ID_VAL         0x000b  /* 16bit */
+
+#define VSE_CVP_STATUS                  0x21c   /* 32bit */
+#define VSE_CVP_STATUS_CFG_RDY          BIT(18) /* CVP_CONFIG_READY */
+#define VSE_CVP_STATUS_CFG_ERR          BIT(19) /* CVP_CONFIG_ERROR */
+#define VSE_CVP_STATUS_CVP_EN           BIT(20) /* ctrl block is enabling CVP */
+#define VSE_CVP_STATUS_USERMODE         BIT(21) /* USERMODE */
+#define VSE_CVP_STATUS_CFG_DONE         BIT(23) /* CVP_CONFIG_DONE */
+#define VSE_CVP_STATUS_PLD_CLK_IN_USE   BIT(24) /* PLD_CLK_IN_USE */
+
+#define VSE_CVP_MODE_CTRL               0x220   /* 32bit */
+#define VSE_CVP_MODE_CTRL_CVP_MODE      BIT(0)  /* CVP (1) or normal mode (0) */
+#define VSE_CVP_MODE_CTRL_HIP_CLK_SEL   BIT(1) /* PMA (1) or fabric clock (0) */
+#define VSE_CVP_MODE_CTRL_NUMCLKS_OFF   8       /* NUMCLKS bits offset */
+#define VSE_CVP_MODE_CTRL_NUMCLKS_MASK  GENMASK(15, 8)
+
+#define VSE_CVP_DATA                    0x228   /* 32bit */
+#define VSE_CVP_PROG_CTRL               0x22c   /* 32bit */
+#define VSE_CVP_PROG_CTRL_CONFIG        BIT(0)
+#define VSE_CVP_PROG_CTRL_START_XFER    BIT(1)
+
+#define VSE_UNCOR_ERR_STATUS            0x234   /* 32bit */
+#define VSE_UNCOR_ERR_CVP_CFG_ERR       BIT(5)  /* CVP_CONFIG_ERROR_LATCHED */
+
+#define DRV_NAME                "altera-cvp"
+#define ALTERA_CVP_MGR_NAME     "Altera CvP FPGA Manager"
+
+/* Optional CvP config error status check for debugging */
+static bool altera_cvp_chkcfg;
+
+struct altera_cvp_conf {
+        struct fpga_manager     *mgr;
+        struct pci_dev          *pci_dev;
+        void __iomem            *map;
+        void                    (*write_data)(struct altera_cvp_conf *, u32);
+        char                    mgr_name[64];
+        u8                      numclks;
+};
+
+static enum fpga_mgr_states altera_cvp_state(struct fpga_manager *mgr)
+{
+        struct altera_cvp_conf *conf = mgr->priv;
+        u32 status;
+
+        pci_read_config_dword(conf->pci_dev, VSE_CVP_STATUS, &status);
+
+        if (status & VSE_CVP_STATUS_CFG_DONE)
+                return FPGA_MGR_STATE_OPERATING;
+
+        if (status & VSE_CVP_STATUS_CVP_EN)
+                return FPGA_MGR_STATE_POWER_UP;
+
+        return FPGA_MGR_STATE_UNKNOWN;
+}
+
+static void altera_cvp_write_data_iomem(struct altera_cvp_conf *conf, u32 val)
+{
+        writel(val, conf->map);
+}
+
+static void altera_cvp_write_data_config(struct altera_cvp_conf *conf, u32 val)
+{
+        pci_write_config_dword(conf->pci_dev, VSE_CVP_DATA, val);
+}
+
+/* switches between CvP clock and internal clock */
+static void altera_cvp_dummy_write(struct altera_cvp_conf *conf)
+{
+        unsigned int i;
+        u32 val;
+
+        /* set 1 CVP clock cycle for every CVP Data Register Write */
+        pci_read_config_dword(conf->pci_dev, VSE_CVP_MODE_CTRL, &val);
+        val &= ~VSE_CVP_MODE_CTRL_NUMCLKS_MASK;
+        val |= 1 << VSE_CVP_MODE_CTRL_NUMCLKS_OFF;
+        pci_write_config_dword(conf->pci_dev, VSE_CVP_MODE_CTRL, val);
+
+        for (i = 0; i < CVP_DUMMY_WR; i++)
+                conf->write_data(conf, 0); /* dummy data, could be any value */
+}
+
+static int altera_cvp_wait_status(struct altera_cvp_conf *conf, u32 status_mask,
+                                  u32 status_val, int timeout_us)
+{
+        unsigned int retries;
+        u32 val;
+
+        retries = timeout_us / 10;
+        if (timeout_us % 10)
+                retries++;
+
+        do {
+                pci_read_config_dword(conf->pci_dev, VSE_CVP_STATUS, &val);
+                if ((val & status_mask) == status_val)
+                        return 0;
+
+                /* use small usleep value to re-check and break early */
+                usleep_range(10, 11);
+        } while (--retries);
+
+        return -ETIMEDOUT;
+}
+
+static int altera_cvp_teardown(struct fpga_manager *mgr,
+                               struct fpga_image_info *info)
+{
+        struct altera_cvp_conf *conf = mgr->priv;
+        struct pci_dev *pdev = conf->pci_dev;
+        int ret;
+        u32 val;
+
+        /* STEP 12 - reset START_XFER bit */
+        pci_read_config_dword(pdev, VSE_CVP_PROG_CTRL, &val);
+        val &= ~VSE_CVP_PROG_CTRL_START_XFER;
+        pci_write_config_dword(pdev, VSE_CVP_PROG_CTRL, val);
+
+        /* STEP 13 - reset CVP_CONFIG bit */
+        val &= ~VSE_CVP_PROG_CTRL_CONFIG;
+        pci_write_config_dword(pdev, VSE_CVP_PROG_CTRL, val);
+
+        /*
+         * STEP 14
+         * - set CVP_NUMCLKS to 1 and then issue CVP_DUMMY_WR dummy
+         *   writes to the HIP
+         */
+        altera_cvp_dummy_write(conf); /* from CVP clock to internal clock */
+
+        /* STEP 15 - poll CVP_CONFIG_READY bit for 0 with 10us timeout */
+        ret = altera_cvp_wait_status(conf, VSE_CVP_STATUS_CFG_RDY, 0, 10);
+        if (ret)
+                dev_err(&mgr->dev, "CFG_RDY == 0 timeout\n");
+
+        return ret;
+}
+
+static int altera_cvp_write_init(struct fpga_manager *mgr,
+                                 struct fpga_image_info *info,
+                                 const char *buf, size_t count)
+{
+        struct altera_cvp_conf *conf = mgr->priv;
+        struct pci_dev *pdev = conf->pci_dev;
+        u32 iflags, val;
+        int ret;
+
+        iflags = info ? info->flags : 0;
+
+        if (iflags & FPGA_MGR_PARTIAL_RECONFIG) {
+                dev_err(&mgr->dev, "Partial reconfiguration not supported.\n");
+                return -EINVAL;
+        }
+
+        /* Determine allowed clock to data ratio */
+        if (iflags & FPGA_MGR_COMPRESSED_BITSTREAM)
+                conf->numclks = 8; /* ratio for all compressed images */
+        else if (iflags & FPGA_MGR_ENCRYPTED_BITSTREAM)
+                conf->numclks = 4; /* for uncompressed and encrypted images */
+        else
+                conf->numclks = 1; /* for uncompressed and unencrypted images */
+
+        /* STEP 1 - read CVP status and check CVP_EN flag */
+        pci_read_config_dword(pdev, VSE_CVP_STATUS, &val);
+        if (!(val & VSE_CVP_STATUS_CVP_EN)) {
+                dev_err(&mgr->dev, "CVP mode off: 0x%04x\n", val);
+                return -ENODEV;
+        }
+
+        if (val & VSE_CVP_STATUS_CFG_RDY) {
+                dev_warn(&mgr->dev, "CvP already started, teardown first\n");
+                ret = altera_cvp_teardown(mgr, info);
+                if (ret)
+                        return ret;
+        }
+
+        /*
+         * STEP 2
+         * - set HIP_CLK_SEL and CVP_MODE (must be set in the order mentioned)
+         */
+        /* switch from fabric to PMA clock */
+        pci_read_config_dword(pdev, VSE_CVP_MODE_CTRL, &val);
+        val |= VSE_CVP_MODE_CTRL_HIP_CLK_SEL;
+        pci_write_config_dword(pdev, VSE_CVP_MODE_CTRL, val);
+
+        /* set CVP mode */
+        pci_read_config_dword(pdev, VSE_CVP_MODE_CTRL, &val);
+        val |= VSE_CVP_MODE_CTRL_CVP_MODE;
+        pci_write_config_dword(pdev, VSE_CVP_MODE_CTRL, val);
+
+        /*
+         * STEP 3
+         * - set CVP_NUMCLKS to 1 and issue CVP_DUMMY_WR dummy writes to the HIP
+         */
+        altera_cvp_dummy_write(conf);
+
+        /* STEP 4 - set CVP_CONFIG bit */
+        pci_read_config_dword(pdev, VSE_CVP_PROG_CTRL, &val);
+        /* request control block to begin transfer using CVP */
+        val |= VSE_CVP_PROG_CTRL_CONFIG;
+        pci_write_config_dword(pdev, VSE_CVP_PROG_CTRL, val);
+
+        /* STEP 5 - poll CVP_CONFIG READY for 1 with 10us timeout */
+        ret = altera_cvp_wait_status(conf, VSE_CVP_STATUS_CFG_RDY,
+                                     VSE_CVP_STATUS_CFG_RDY, 10);
+        if (ret) {
+                dev_warn(&mgr->dev, "CFG_RDY == 1 timeout\n");
+                return ret;
+        }
+
+        /*
+         * STEP 6
+         * - set CVP_NUMCLKS to 1 and issue CVP_DUMMY_WR dummy writes to the HIP
+         */
+        altera_cvp_dummy_write(conf);
+
+        /* STEP 7 - set START_XFER */
+        pci_read_config_dword(pdev, VSE_CVP_PROG_CTRL, &val);
+        val |= VSE_CVP_PROG_CTRL_START_XFER;
+        pci_write_config_dword(pdev, VSE_CVP_PROG_CTRL, val);
+
+        /* STEP 8 - start transfer (set CVP_NUMCLKS for bitstream) */
+        pci_read_config_dword(pdev, VSE_CVP_MODE_CTRL, &val);
+        val &= ~VSE_CVP_MODE_CTRL_NUMCLKS_MASK;
+        val |= conf->numclks << VSE_CVP_MODE_CTRL_NUMCLKS_OFF;
+        pci_write_config_dword(pdev, VSE_CVP_MODE_CTRL, val);
+
+        return 0;
+}
+
+static inline int altera_cvp_chk_error(struct fpga_manager *mgr, size_t bytes)
+{
+        struct altera_cvp_conf *conf = mgr->priv;
+        u32 val;
+
+        /* STEP 10 (optional) - check CVP_CONFIG_ERROR flag */
+        pci_read_config_dword(conf->pci_dev, VSE_CVP_STATUS, &val);
+        if (val & VSE_CVP_STATUS_CFG_ERR) {
+                dev_err(&mgr->dev, "CVP_CONFIG_ERROR after %zu bytes!\n",
+                        bytes);
+                return -EPROTO;
+        }
+        return 0;
+}
+
+static int altera_cvp_write(struct fpga_manager *mgr, const char *buf,
+                            size_t count)
+{
+        struct altera_cvp_conf *conf = mgr->priv;
+        const u32 *data;
+        size_t done, remaining;
+        int status = 0;
+        u32 mask;
+
+        /* STEP 9 - write 32-bit data from RBF file to CVP data register */
+        data = (u32 *)buf;
+        remaining = count;
+        done = 0;
+
+        while (remaining >= 4) {
+                conf->write_data(conf, *data++);
+                done += 4;
+                remaining -= 4;
+
+                /*
+                 * STEP 10 (optional) and STEP 11
+                 * - check error flag
+                 * - loop until data transfer completed
+                 * Config images can be huge (more than 40 MiB), so
+                 * only check after a new 4k data block has been written.
+                 * This reduces the number of checks and speeds up the
+                 * configuration process.
+                 */
+                if (altera_cvp_chkcfg && !(done % SZ_4K)) {
+                        status = altera_cvp_chk_error(mgr, done);
+                        if (status < 0)
+                                return status;
+                }
+        }
+
+        /* write up to 3 trailing bytes, if any */
+        mask = BIT(remaining * 8) - 1;
+        if (mask)
+                conf->write_data(conf, *data & mask);
+
+        if (altera_cvp_chkcfg)
+                status = altera_cvp_chk_error(mgr, count);
+
+        return status;
+}
+
+static int altera_cvp_write_complete(struct fpga_manager *mgr,
+                                     struct fpga_image_info *info)
+{
+        struct altera_cvp_conf *conf = mgr->priv;
+        struct pci_dev *pdev = conf->pci_dev;
+        int ret;
+        u32 mask;
+        u32 val;
+
+        ret = altera_cvp_teardown(mgr, info);
+        if (ret)
+                return ret;
+
+        /* STEP 16 - check CVP_CONFIG_ERROR_LATCHED bit */
+        pci_read_config_dword(pdev, VSE_UNCOR_ERR_STATUS, &val);
+        if (val & VSE_UNCOR_ERR_CVP_CFG_ERR) {
+                dev_err(&mgr->dev, "detected CVP_CONFIG_ERROR_LATCHED!\n");
+                return -EPROTO;
+        }
+
+        /* STEP 17 - reset CVP_MODE and HIP_CLK_SEL bit */
+        pci_read_config_dword(pdev, VSE_CVP_MODE_CTRL, &val);
+        val &= ~VSE_CVP_MODE_CTRL_HIP_CLK_SEL;
+        val &= ~VSE_CVP_MODE_CTRL_CVP_MODE;
+        pci_write_config_dword(pdev, VSE_CVP_MODE_CTRL, val);
+
+        /* STEP 18 - poll PLD_CLK_IN_USE and USER_MODE bits */
+        mask = VSE_CVP_STATUS_PLD_CLK_IN_USE | VSE_CVP_STATUS_USERMODE;
+        ret = altera_cvp_wait_status(conf, mask, mask, TIMEOUT_US);
+        if (ret)
+                dev_err(&mgr->dev, "PLD_CLK_IN_USE|USERMODE timeout\n");
+
+        return ret;
+}
+
+static const struct fpga_manager_ops altera_cvp_ops = {
+        .state          = altera_cvp_state,
+        .write_init     = altera_cvp_write_init,
+        .write          = altera_cvp_write,
+        .write_complete = altera_cvp_write_complete,
+};
+
+static ssize_t show_chkcfg(struct device_driver *dev, char *buf)
+{
+        return snprintf(buf, 3, "%d\n", altera_cvp_chkcfg);
+}
+
+static ssize_t store_chkcfg(struct device_driver *drv, const char *buf,
+                            size_t count)
+{
+        int ret;
+
+        ret = kstrtobool(buf, &altera_cvp_chkcfg);
+        if (ret)
+                return ret;
+
+        return count;
+}
+
+static DRIVER_ATTR(chkcfg, 0600, show_chkcfg, store_chkcfg);
+
+static int altera_cvp_probe(struct pci_dev *pdev,
+                            const struct pci_device_id *dev_id);
+static void altera_cvp_remove(struct pci_dev *pdev);
+
+#define PCI_VENDOR_ID_ALTERA    0x1172
+
+static struct pci_device_id altera_cvp_id_tbl[] = {
+        { PCI_VDEVICE(ALTERA, PCI_ANY_ID) },
+        { }
+};
+MODULE_DEVICE_TABLE(pci, altera_cvp_id_tbl);
+
+static struct pci_driver altera_cvp_driver = {
+        .name   = DRV_NAME,
+        .id_table = altera_cvp_id_tbl,
+        .probe  = altera_cvp_probe,
+        .remove = altera_cvp_remove,
+};
+
+static int altera_cvp_probe(struct pci_dev *pdev,
+                            const struct pci_device_id *dev_id)
+{
+        struct altera_cvp_conf *conf;
+        u16 cmd, val;
+        int ret;
+
+        /*
+         * First check if this is the expected FPGA device. PCI config
+         * space access works without enabling the PCI device, memory
+         * space access is enabled further down.
+         */
+        pci_read_config_word(pdev, VSE_PCIE_EXT_CAP_ID, &val);
+        if (val != VSE_PCIE_EXT_CAP_ID_VAL) {
+                dev_err(&pdev->dev, "Wrong EXT_CAP_ID value 0x%x\n", val);
+                return -ENODEV;
+        }
+
+        conf = devm_kzalloc(&pdev->dev, sizeof(*conf), GFP_KERNEL);
+        if (!conf)
+                return -ENOMEM;
+
+        /*
+         * Enable memory BAR access. We cannot use pci_enable_device() here
+         * because it will make the driver unusable with FPGA devices that
+         * have additional big IOMEM resources (e.g. 4GiB BARs) on 32-bit
+         * platform. Such BARs will not have an assigned address range and
+         * pci_enable_device() will fail, complaining about not claimed BAR,
+         * even if the concerned BAR is not needed for FPGA configuration
+         * at all. Thus, enable the device via PCI config space command.
+         */
+        pci_read_config_word(pdev, PCI_COMMAND, &cmd);
+        if (!(cmd & PCI_COMMAND_MEMORY)) {
+                cmd |= PCI_COMMAND_MEMORY;
+                pci_write_config_word(pdev, PCI_COMMAND, cmd);
+        }
+
+        ret = pci_request_region(pdev, CVP_BAR, "CVP");
+        if (ret) {
+                dev_err(&pdev->dev, "Requesting CVP BAR region failed\n");
+                goto err_disable;
+        }
+
+        conf->pci_dev = pdev;
+        conf->write_data = altera_cvp_write_data_iomem;
+
+        conf->map = pci_iomap(pdev, CVP_BAR, 0);
+        if (!conf->map) {
+                dev_warn(&pdev->dev, "Mapping CVP BAR failed\n");
+                conf->write_data = altera_cvp_write_data_config;
+        }
+
+        snprintf(conf->mgr_name, sizeof(conf->mgr_name), "%s @%s",
+                 ALTERA_CVP_MGR_NAME, pci_name(pdev));
+
+        ret = fpga_mgr_register(&pdev->dev, conf->mgr_name,
+                                &altera_cvp_ops, conf);
+        if (ret)
+                goto err_unmap;
+
+        ret = driver_create_file(&altera_cvp_driver.driver,
+                                 &driver_attr_chkcfg);
+        if (ret) {
+                dev_err(&pdev->dev, "Can't create sysfs chkcfg file\n");
+                fpga_mgr_unregister(&pdev->dev);
+                goto err_unmap;
+        }
+
+        return 0;
+
+err_unmap:
+        pci_iounmap(pdev, conf->map);
+        pci_release_region(pdev, CVP_BAR);
+err_disable:
+        cmd &= ~PCI_COMMAND_MEMORY;
+        pci_write_config_word(pdev, PCI_COMMAND, cmd);
+        return ret;
+}
+
+static void altera_cvp_remove(struct pci_dev *pdev)
+{
+        struct fpga_manager *mgr = pci_get_drvdata(pdev);
+        struct altera_cvp_conf *conf = mgr->priv;
+        u16 cmd;
+
+        driver_remove_file(&altera_cvp_driver.driver, &driver_attr_chkcfg);
+        fpga_mgr_unregister(&pdev->dev);
+        pci_iounmap(pdev, conf->map);
+        pci_release_region(pdev, CVP_BAR);
+        pci_read_config_word(pdev, PCI_COMMAND, &cmd);
+        cmd &= ~PCI_COMMAND_MEMORY;
+        pci_write_config_word(pdev, PCI_COMMAND, cmd);
+}
+
+module_pci_driver(altera_cvp_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Anatolij Gustschin <agust@denx.de>");
+MODULE_DESCRIPTION("Module to load Altera FPGA over CvP");