diff options
Diffstat (limited to 'drivers/fpga/altera-pr-ip-core.c')
-rw-r--r-- | drivers/fpga/altera-pr-ip-core.c | 201 |
1 files changed, 201 insertions, 0 deletions
diff --git a/drivers/fpga/altera-pr-ip-core.c b/drivers/fpga/altera-pr-ip-core.c new file mode 100644 index 000000000..df8671af4 --- /dev/null +++ b/drivers/fpga/altera-pr-ip-core.c @@ -0,0 +1,201 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Driver for Altera Partial Reconfiguration IP Core + * + * Copyright (C) 2016-2017 Intel Corporation + * + * Based on socfpga-a10.c Copyright (C) 2015-2016 Altera Corporation + * by Alan Tull <atull@opensource.altera.com> + */ +#include <linux/delay.h> +#include <linux/fpga/altera-pr-ip-core.h> +#include <linux/fpga/fpga-mgr.h> +#include <linux/module.h> + +#define ALT_PR_DATA_OFST 0x00 +#define ALT_PR_CSR_OFST 0x04 + +#define ALT_PR_CSR_PR_START BIT(0) +#define ALT_PR_CSR_STATUS_SFT 2 +#define ALT_PR_CSR_STATUS_MSK (7 << ALT_PR_CSR_STATUS_SFT) +#define ALT_PR_CSR_STATUS_NRESET (0 << ALT_PR_CSR_STATUS_SFT) +#define ALT_PR_CSR_STATUS_PR_ERR (1 << ALT_PR_CSR_STATUS_SFT) +#define ALT_PR_CSR_STATUS_CRC_ERR (2 << ALT_PR_CSR_STATUS_SFT) +#define ALT_PR_CSR_STATUS_BAD_BITS (3 << ALT_PR_CSR_STATUS_SFT) +#define ALT_PR_CSR_STATUS_PR_IN_PROG (4 << ALT_PR_CSR_STATUS_SFT) +#define ALT_PR_CSR_STATUS_PR_SUCCESS (5 << ALT_PR_CSR_STATUS_SFT) + +struct alt_pr_priv { + void __iomem *reg_base; +}; + +static enum fpga_mgr_states alt_pr_fpga_state(struct fpga_manager *mgr) +{ + struct alt_pr_priv *priv = mgr->priv; + const char *err = "unknown"; + enum fpga_mgr_states ret = FPGA_MGR_STATE_UNKNOWN; + u32 val; + + val = readl(priv->reg_base + ALT_PR_CSR_OFST); + + val &= ALT_PR_CSR_STATUS_MSK; + + switch (val) { + case ALT_PR_CSR_STATUS_NRESET: + return FPGA_MGR_STATE_RESET; + + case ALT_PR_CSR_STATUS_PR_ERR: + err = "pr error"; + ret = FPGA_MGR_STATE_WRITE_ERR; + break; + + case ALT_PR_CSR_STATUS_CRC_ERR: + err = "crc error"; + ret = FPGA_MGR_STATE_WRITE_ERR; + break; + + case ALT_PR_CSR_STATUS_BAD_BITS: + err = "bad bits"; + ret = FPGA_MGR_STATE_WRITE_ERR; + break; + + case ALT_PR_CSR_STATUS_PR_IN_PROG: + return FPGA_MGR_STATE_WRITE; + + case ALT_PR_CSR_STATUS_PR_SUCCESS: + return FPGA_MGR_STATE_OPERATING; + + default: + break; + } + + dev_err(&mgr->dev, "encountered error code %d (%s) in %s()\n", + val, err, __func__); + return ret; +} + +static int alt_pr_fpga_write_init(struct fpga_manager *mgr, + struct fpga_image_info *info, + const char *buf, size_t count) +{ + struct alt_pr_priv *priv = mgr->priv; + u32 val; + + if (!(info->flags & FPGA_MGR_PARTIAL_RECONFIG)) { + dev_err(&mgr->dev, "%s Partial Reconfiguration flag not set\n", + __func__); + return -EINVAL; + } + + val = readl(priv->reg_base + ALT_PR_CSR_OFST); + + if (val & ALT_PR_CSR_PR_START) { + dev_err(&mgr->dev, + "%s Partial Reconfiguration already started\n", + __func__); + return -EINVAL; + } + + writel(val | ALT_PR_CSR_PR_START, priv->reg_base + ALT_PR_CSR_OFST); + + return 0; +} + +static int alt_pr_fpga_write(struct fpga_manager *mgr, const char *buf, + size_t count) +{ + struct alt_pr_priv *priv = mgr->priv; + u32 *buffer_32 = (u32 *)buf; + size_t i = 0; + + if (!count) + return -EINVAL; + + /* Write out the complete 32-bit chunks */ + while (count >= sizeof(u32)) { + writel(buffer_32[i++], priv->reg_base); + count -= sizeof(u32); + } + + /* Write out remaining non 32-bit chunks */ + switch (count) { + case 3: + writel(buffer_32[i++] & 0x00ffffff, priv->reg_base); + break; + case 2: + writel(buffer_32[i++] & 0x0000ffff, priv->reg_base); + break; + case 1: + writel(buffer_32[i++] & 0x000000ff, priv->reg_base); + break; + case 0: + break; + default: + /* This will never happen */ + return -EFAULT; + } + + if (alt_pr_fpga_state(mgr) == FPGA_MGR_STATE_WRITE_ERR) + return -EIO; + + return 0; +} + +static int alt_pr_fpga_write_complete(struct fpga_manager *mgr, + struct fpga_image_info *info) +{ + u32 i = 0; + + do { + switch (alt_pr_fpga_state(mgr)) { + case FPGA_MGR_STATE_WRITE_ERR: + return -EIO; + + case FPGA_MGR_STATE_OPERATING: + dev_info(&mgr->dev, + "successful partial reconfiguration\n"); + return 0; + + default: + break; + } + udelay(1); + } while (info->config_complete_timeout_us > i++); + + dev_err(&mgr->dev, "timed out waiting for write to complete\n"); + return -ETIMEDOUT; +} + +static const struct fpga_manager_ops alt_pr_ops = { + .state = alt_pr_fpga_state, + .write_init = alt_pr_fpga_write_init, + .write = alt_pr_fpga_write, + .write_complete = alt_pr_fpga_write_complete, +}; + +int alt_pr_register(struct device *dev, void __iomem *reg_base) +{ + struct alt_pr_priv *priv; + struct fpga_manager *mgr; + u32 val; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->reg_base = reg_base; + + val = readl(priv->reg_base + ALT_PR_CSR_OFST); + + dev_dbg(dev, "%s status=%d start=%d\n", __func__, + (val & ALT_PR_CSR_STATUS_MSK) >> ALT_PR_CSR_STATUS_SFT, + (int)(val & ALT_PR_CSR_PR_START)); + + mgr = devm_fpga_mgr_register(dev, dev_name(dev), &alt_pr_ops, priv); + return PTR_ERR_OR_ZERO(mgr); +} +EXPORT_SYMBOL_GPL(alt_pr_register); + +MODULE_AUTHOR("Matthew Gerlach <matthew.gerlach@linux.intel.com>"); +MODULE_DESCRIPTION("Altera Partial Reconfiguration IP Core"); +MODULE_LICENSE("GPL v2"); |