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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/fpga/microchip-spi.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/fpga/microchip-spi.c')
-rw-r--r-- | drivers/fpga/microchip-spi.c | 402 |
1 files changed, 402 insertions, 0 deletions
diff --git a/drivers/fpga/microchip-spi.c b/drivers/fpga/microchip-spi.c new file mode 100644 index 000000000..137fafdf5 --- /dev/null +++ b/drivers/fpga/microchip-spi.c @@ -0,0 +1,402 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Microchip Polarfire FPGA programming over slave SPI interface. + */ + +#include <asm/unaligned.h> +#include <linux/delay.h> +#include <linux/fpga/fpga-mgr.h> +#include <linux/iopoll.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/spi/spi.h> + +#define MPF_SPI_ISC_ENABLE 0x0B +#define MPF_SPI_ISC_DISABLE 0x0C +#define MPF_SPI_READ_STATUS 0x00 +#define MPF_SPI_READ_DATA 0x01 +#define MPF_SPI_FRAME_INIT 0xAE +#define MPF_SPI_FRAME 0xEE +#define MPF_SPI_PRG_MODE 0x01 +#define MPF_SPI_RELEASE 0x23 + +#define MPF_SPI_FRAME_SIZE 16 + +#define MPF_HEADER_SIZE_OFFSET 24 +#define MPF_DATA_SIZE_OFFSET 55 + +#define MPF_LOOKUP_TABLE_RECORD_SIZE 9 +#define MPF_LOOKUP_TABLE_BLOCK_ID_OFFSET 0 +#define MPF_LOOKUP_TABLE_BLOCK_START_OFFSET 1 + +#define MPF_COMPONENTS_SIZE_ID 5 +#define MPF_BITSTREAM_ID 8 + +#define MPF_BITS_PER_COMPONENT_SIZE 22 + +#define MPF_STATUS_POLL_TIMEOUT (2 * USEC_PER_SEC) +#define MPF_STATUS_BUSY BIT(0) +#define MPF_STATUS_READY BIT(1) +#define MPF_STATUS_SPI_VIOLATION BIT(2) +#define MPF_STATUS_SPI_ERROR BIT(3) + +struct mpf_priv { + struct spi_device *spi; + bool program_mode; + u8 tx __aligned(ARCH_KMALLOC_MINALIGN); + u8 rx; +}; + +static int mpf_read_status(struct mpf_priv *priv) +{ + /* + * HW status is returned on MISO in the first byte after CS went + * active. However, first reading can be inadequate, so we submit + * two identical SPI transfers and use result of the later one. + */ + struct spi_transfer xfers[2] = { + { + .tx_buf = &priv->tx, + .rx_buf = &priv->rx, + .len = 1, + .cs_change = 1, + }, { + .tx_buf = &priv->tx, + .rx_buf = &priv->rx, + .len = 1, + }, + }; + u8 status; + int ret; + + priv->tx = MPF_SPI_READ_STATUS; + + ret = spi_sync_transfer(priv->spi, xfers, 2); + if (ret) + return ret; + + status = priv->rx; + + if ((status & MPF_STATUS_SPI_VIOLATION) || + (status & MPF_STATUS_SPI_ERROR)) + return -EIO; + + return status; +} + +static enum fpga_mgr_states mpf_ops_state(struct fpga_manager *mgr) +{ + struct mpf_priv *priv = mgr->priv; + bool program_mode; + int status; + + program_mode = priv->program_mode; + status = mpf_read_status(priv); + + if (!program_mode && !status) + return FPGA_MGR_STATE_OPERATING; + + return FPGA_MGR_STATE_UNKNOWN; +} + +static int mpf_ops_parse_header(struct fpga_manager *mgr, + struct fpga_image_info *info, + const char *buf, size_t count) +{ + size_t component_size_byte_num, component_size_byte_off, + components_size_start, bitstream_start, + block_id_offset, block_start_offset; + u8 header_size, blocks_num, block_id; + u32 block_start, component_size; + u16 components_num, i; + + if (!buf) { + dev_err(&mgr->dev, "Image buffer is not provided\n"); + return -EINVAL; + } + + header_size = *(buf + MPF_HEADER_SIZE_OFFSET); + if (header_size > count) { + info->header_size = header_size; + return -EAGAIN; + } + + /* + * Go through look-up table to find out where actual bitstream starts + * and where sizes of components of the bitstream lies. + */ + blocks_num = *(buf + header_size - 1); + block_id_offset = header_size + MPF_LOOKUP_TABLE_BLOCK_ID_OFFSET; + block_start_offset = header_size + MPF_LOOKUP_TABLE_BLOCK_START_OFFSET; + + header_size += blocks_num * MPF_LOOKUP_TABLE_RECORD_SIZE; + if (header_size > count) { + info->header_size = header_size; + return -EAGAIN; + } + + components_size_start = 0; + bitstream_start = 0; + + while (blocks_num--) { + block_id = *(buf + block_id_offset); + block_start = get_unaligned_le32(buf + block_start_offset); + + switch (block_id) { + case MPF_BITSTREAM_ID: + bitstream_start = block_start; + info->header_size = block_start; + if (block_start > count) + return -EAGAIN; + + break; + case MPF_COMPONENTS_SIZE_ID: + components_size_start = block_start; + break; + default: + break; + } + + if (bitstream_start && components_size_start) + break; + + block_id_offset += MPF_LOOKUP_TABLE_RECORD_SIZE; + block_start_offset += MPF_LOOKUP_TABLE_RECORD_SIZE; + } + + if (!bitstream_start || !components_size_start) { + dev_err(&mgr->dev, "Failed to parse header look-up table\n"); + return -EFAULT; + } + + /* + * Parse bitstream size. + * Sizes of components of the bitstream are 22-bits long placed next + * to each other. Image header should be extended by now up to where + * actual bitstream starts, so no need for overflow check anymore. + */ + components_num = get_unaligned_le16(buf + MPF_DATA_SIZE_OFFSET); + + for (i = 0; i < components_num; i++) { + component_size_byte_num = + (i * MPF_BITS_PER_COMPONENT_SIZE) / BITS_PER_BYTE; + component_size_byte_off = + (i * MPF_BITS_PER_COMPONENT_SIZE) % BITS_PER_BYTE; + + component_size = get_unaligned_le32(buf + + components_size_start + + component_size_byte_num); + component_size >>= component_size_byte_off; + component_size &= GENMASK(MPF_BITS_PER_COMPONENT_SIZE - 1, 0); + + info->data_size += component_size * MPF_SPI_FRAME_SIZE; + } + + return 0; +} + +static int mpf_poll_status(struct mpf_priv *priv, u8 mask) +{ + int ret, status; + + /* + * Busy poll HW status. Polling stops if any of the following + * conditions are met: + * - timeout is reached + * - mpf_read_status() returns an error + * - busy bit is cleared AND mask bits are set + */ + ret = read_poll_timeout(mpf_read_status, status, + (status < 0) || + ((status & (MPF_STATUS_BUSY | mask)) == mask), + 0, MPF_STATUS_POLL_TIMEOUT, false, priv); + if (ret < 0) + return ret; + + return status; +} + +static int mpf_spi_write(struct mpf_priv *priv, const void *buf, size_t buf_size) +{ + int status = mpf_poll_status(priv, 0); + + if (status < 0) + return status; + + return spi_write_then_read(priv->spi, buf, buf_size, NULL, 0); +} + +static int mpf_spi_write_then_read(struct mpf_priv *priv, + const void *txbuf, size_t txbuf_size, + void *rxbuf, size_t rxbuf_size) +{ + const u8 read_command[] = { MPF_SPI_READ_DATA }; + int ret; + + ret = mpf_spi_write(priv, txbuf, txbuf_size); + if (ret) + return ret; + + ret = mpf_poll_status(priv, MPF_STATUS_READY); + if (ret < 0) + return ret; + + return spi_write_then_read(priv->spi, read_command, sizeof(read_command), + rxbuf, rxbuf_size); +} + +static int mpf_ops_write_init(struct fpga_manager *mgr, + struct fpga_image_info *info, const char *buf, + size_t count) +{ + const u8 program_mode[] = { MPF_SPI_FRAME_INIT, MPF_SPI_PRG_MODE }; + const u8 isc_en_command[] = { MPF_SPI_ISC_ENABLE }; + struct mpf_priv *priv = mgr->priv; + struct device *dev = &mgr->dev; + u32 isc_ret = 0; + int ret; + + if (info->flags & FPGA_MGR_PARTIAL_RECONFIG) { + dev_err(dev, "Partial reconfiguration is not supported\n"); + return -EOPNOTSUPP; + } + + ret = mpf_spi_write_then_read(priv, isc_en_command, sizeof(isc_en_command), + &isc_ret, sizeof(isc_ret)); + if (ret || isc_ret) { + dev_err(dev, "Failed to enable ISC: spi_ret %d, isc_ret %u\n", + ret, isc_ret); + return -EFAULT; + } + + ret = mpf_spi_write(priv, program_mode, sizeof(program_mode)); + if (ret) { + dev_err(dev, "Failed to enter program mode: %d\n", ret); + return ret; + } + + priv->program_mode = true; + + return 0; +} + +static int mpf_ops_write(struct fpga_manager *mgr, const char *buf, size_t count) +{ + struct spi_transfer xfers[2] = { 0 }; + struct mpf_priv *priv = mgr->priv; + struct device *dev = &mgr->dev; + int ret, i; + + if (count % MPF_SPI_FRAME_SIZE) { + dev_err(dev, "Bitstream size is not a multiple of %d\n", + MPF_SPI_FRAME_SIZE); + return -EINVAL; + } + + xfers[0].tx_buf = &priv->tx; + xfers[0].len = 1; + + for (i = 0; i < count / MPF_SPI_FRAME_SIZE; i++) { + xfers[1].tx_buf = buf + i * MPF_SPI_FRAME_SIZE; + xfers[1].len = MPF_SPI_FRAME_SIZE; + + ret = mpf_poll_status(priv, 0); + if (ret >= 0) { + priv->tx = MPF_SPI_FRAME; + ret = spi_sync_transfer(priv->spi, xfers, ARRAY_SIZE(xfers)); + } + + if (ret) { + dev_err(dev, "Failed to write bitstream frame %d/%zu\n", + i, count / MPF_SPI_FRAME_SIZE); + return ret; + } + } + + return 0; +} + +static int mpf_ops_write_complete(struct fpga_manager *mgr, + struct fpga_image_info *info) +{ + const u8 isc_dis_command[] = { MPF_SPI_ISC_DISABLE }; + const u8 release_command[] = { MPF_SPI_RELEASE }; + struct mpf_priv *priv = mgr->priv; + struct device *dev = &mgr->dev; + int ret; + + ret = mpf_spi_write(priv, isc_dis_command, sizeof(isc_dis_command)); + if (ret) { + dev_err(dev, "Failed to disable ISC: %d\n", ret); + return ret; + } + + usleep_range(1000, 2000); + + ret = mpf_spi_write(priv, release_command, sizeof(release_command)); + if (ret) { + dev_err(dev, "Failed to exit program mode: %d\n", ret); + return ret; + } + + priv->program_mode = false; + + return 0; +} + +static const struct fpga_manager_ops mpf_ops = { + .state = mpf_ops_state, + .initial_header_size = 71, + .skip_header = true, + .parse_header = mpf_ops_parse_header, + .write_init = mpf_ops_write_init, + .write = mpf_ops_write, + .write_complete = mpf_ops_write_complete, +}; + +static int mpf_probe(struct spi_device *spi) +{ + struct device *dev = &spi->dev; + struct fpga_manager *mgr; + struct mpf_priv *priv; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->spi = spi; + + mgr = devm_fpga_mgr_register(dev, "Microchip Polarfire SPI FPGA Manager", + &mpf_ops, priv); + + return PTR_ERR_OR_ZERO(mgr); +} + +static const struct spi_device_id mpf_spi_ids[] = { + { .name = "mpf-spi-fpga-mgr", }, + {}, +}; +MODULE_DEVICE_TABLE(spi, mpf_spi_ids); + +#if IS_ENABLED(CONFIG_OF) +static const struct of_device_id mpf_of_ids[] = { + { .compatible = "microchip,mpf-spi-fpga-mgr" }, + {}, +}; +MODULE_DEVICE_TABLE(of, mpf_of_ids); +#endif /* IS_ENABLED(CONFIG_OF) */ + +static struct spi_driver mpf_driver = { + .probe = mpf_probe, + .id_table = mpf_spi_ids, + .driver = { + .name = "microchip_mpf_spi_fpga_mgr", + .of_match_table = of_match_ptr(mpf_of_ids), + }, +}; + +module_spi_driver(mpf_driver); + +MODULE_DESCRIPTION("Microchip Polarfire SPI FPGA Manager"); +MODULE_AUTHOR("Ivan Bornyakov <i.bornyakov@metrotek.ru>"); +MODULE_LICENSE("GPL"); |