On Wed, 30 Nov 2016, Joshua Clayton wrote:
Hi Clayton,
I just have a few minor one line changes below. Only one
is operational, I should have caught that earlier.
> cyclone-ps-spi loads FPGA firmware over spi, using the "passive serial"
> interface on Altera Cyclone FPGAS.
>
> This is one of the simpler ways to set up an FPGA at runtime.
> The signal interface is close to unidirectional spi with lsb first.
>
> Signed-off-by: Joshua Clayton <stillcompiling@xxxxxxxxx>
> ---
> drivers/fpga/Kconfig | 7 ++
> drivers/fpga/Makefile | 1 +
> drivers/fpga/cyclone-ps-spi.c | 176 ++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 184 insertions(+)
> create mode 100644 drivers/fpga/cyclone-ps-spi.c
>
> diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
> index cd84934..2462707 100644
> --- a/drivers/fpga/Kconfig
> +++ b/drivers/fpga/Kconfig
> @@ -13,6 +13,13 @@ config FPGA
>
> if FPGA
>
> +config FPGA_MGR_CYCLONE_PS_SPI
> + tristate "Altera Cyclone FPGA Passive Serial over SPI"
> + depends on SPI
> + help
> + FPGA manager driver support for Altera Cyclone using the
> + passive serial interface over SPI
> +
> config FPGA_MGR_SOCFPGA
> tristate "Altera SOCFPGA FPGA Manager"
> depends on ARCH_SOCFPGA
> diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
> index 8d83fc6..8f93930 100644
> --- a/drivers/fpga/Makefile
> +++ b/drivers/fpga/Makefile
> @@ -6,5 +6,6 @@
> obj-$(CONFIG_FPGA) += fpga-mgr.o
>
> # FPGA Manager Drivers
> +obj-$(CONFIG_FPGA_MGR_CYCLONE_PS_SPI) += cyclone-ps-spi.o
> obj-$(CONFIG_FPGA_MGR_SOCFPGA) += socfpga.o
> obj-$(CONFIG_FPGA_MGR_ZYNQ_FPGA) += zynq-fpga.o
> diff --git a/drivers/fpga/cyclone-ps-spi.c b/drivers/fpga/cyclone-ps-spi.c
> new file mode 100644
> index 0000000..57a520d
> --- /dev/null
> +++ b/drivers/fpga/cyclone-ps-spi.c
> @@ -0,0 +1,176 @@
> +/**
> + * Copyright (c) 2015 United Western Technologies, Corporation
> + *
> + * Joshua Clayton <stillcompiling@xxxxxxxxx>
> + *
> + * Manage Altera fpga firmware that is loaded over spi.
> + * Firmware must be in binary "rbf" format.
> + * Works on Cyclone V. Should work on cyclone series.
> + * May work on other Altera fpgas.
> + *
> + */
> +
> +#include <linux/bitrev.h>
> +#include <linux/delay.h>
> +#include <linux/fpga/fpga-mgr.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/module.h>
> +#include <linux/of_gpio.h>
> +#include <linux/spi/spi.h>
> +#include <linux/sizes.h>
> +
> +#define FPGA_RESET_TIME 50 /* time in usecs to trigger FPGA config */
> +#define FPGA_MIN_DELAY 50 /* min usecs to wait for config status */
> +#define FPGA_MAX_DELAY 1000 /* max usecs to wait for config status */
> +
> +struct cyclonespi_conf {
> + struct gpio_desc *config;
> + struct gpio_desc *status;
> + struct spi_device *spi;
> +};
> +
> +static const struct of_device_id of_ef_match[] = {
> + { .compatible = "altr,cyclone-ps-spi-fpga-mgr", },
> + {}
> +};
> +MODULE_DEVICE_TABLE(of, of_ef_match);
> +
> +static enum fpga_mgr_states cyclonespi_state(struct fpga_manager *mgr)
> +{
> + return mgr->state;
> +}
This function gets called once to initialize mgr->state in
fpga_mgr_register(). So it should at least return the state the FPGA
is at then. If it is unknown, it can just return
FPGA_MGR_STATE_UNKNOWN.
> +
> +static int cyclonespi_write_init(struct fpga_manager *mgr, u32 flags,
> + const char *buf, size_t count)
Minor, but please fix the indentation of 'const' to match that of
'struct' above. checkpatch.pl is probably issuing warnings
about that.
> +{
> + struct cyclonespi_conf *conf = (struct cyclonespi_conf *)mgr->priv;
> + int i;
> +
> + if (flags & FPGA_MGR_PARTIAL_RECONFIG) {
> + dev_err(&mgr->dev, "Partial reconfiguration not supported.\n");
> + return -EINVAL;
> + }
> +
> + gpiod_set_value(conf->config, 0);
> + usleep_range(FPGA_RESET_TIME, FPGA_RESET_TIME + 20);
> + if (gpiod_get_value(conf->status) == 1) {
> + dev_err(&mgr->dev, "Status pin should be low.\n");
> + return -EIO;
> + }
> +
> + gpiod_set_value(conf->config, 1);
> + for (i = 0; i < (FPGA_MAX_DELAY / FPGA_MIN_DELAY); i++) {
> + usleep_range(FPGA_MIN_DELAY, FPGA_MIN_DELAY + 20);
> + if (gpiod_get_value(conf->status))
> + return 0;
> + }
> +
> + dev_err(&mgr->dev, "Status pin not ready.\n");
> + return -EIO;
> +}
> +
> +static void rev_buf(void *buf, size_t len)
> +{
> + u32 *fw32 = (u32 *)buf;
> + const u32 *fw_end = (u32 *)(buf + len);
> +
> + /* set buffer to lsb first */
> + while (fw32 < fw_end) {
> + *fw32 = bitrev8x4(*fw32);
> + fw32++;
> + }
> +}
> +
> +static int cyclonespi_write(struct fpga_manager *mgr, const char *buf,
> + size_t count)
Please fix alignment here also.
> +{
> + struct cyclonespi_conf *conf = (struct cyclonespi_conf *)mgr->priv;
> + const char *fw_data = buf;
> + const char *fw_data_end = fw_data + count;
> +
> + while (fw_data < fw_data_end) {
> + int ret;
> + size_t stride = min(fw_data_end - fw_data, SZ_4K);
> +
> + rev_buf((void *)fw_data, stride);
> + ret = spi_write(conf->spi, fw_data, stride);
> + if (ret) {
> + dev_err(&mgr->dev, "spi error in firmware write: %d\n",
> + ret);
> + return ret;
> + }
> + fw_data += stride;
> + }
> +
> + return 0;
> +}
> +
> +static int cyclonespi_write_complete(struct fpga_manager *mgr, u32 flags)
> +{
> + struct cyclonespi_conf *conf = (struct cyclonespi_conf *)mgr->priv;
> +
> + if (gpiod_get_value(conf->status) == 0) {
> + dev_err(&mgr->dev, "Error during configuration.\n");
> + return -EIO;
> + }
> +
> + return 0;
> +}
> +
> +static const struct fpga_manager_ops cyclonespi_ops = {
> + .state = cyclonespi_state,
> + .write_init = cyclonespi_write_init,
> + .write = cyclonespi_write,
> + .write_complete = cyclonespi_write_complete,
> +};
> +
> +static int cyclonespi_probe(struct spi_device *spi)
> +{
> + struct cyclonespi_conf *conf = devm_kzalloc(&spi->dev, sizeof(*conf),
> + GFP_KERNEL);
> +
> + if (!conf)
> + return -ENOMEM;
> +
> + conf->spi = spi;
> + conf->config = devm_gpiod_get(&spi->dev, "config", GPIOD_OUT_LOW);
> + if (IS_ERR(conf->config)) {
> + dev_err(&spi->dev, "Failed to get config gpio: %ld\n",
> + PTR_ERR(conf->config));
> + return PTR_ERR(conf->config);
> + }
> +
> + conf->status = devm_gpiod_get(&spi->dev, "status", GPIOD_IN);
> + if (IS_ERR(conf->status)) {
> + dev_err(&spi->dev, "Failed to get status gpio: %ld\n",
> + PTR_ERR(conf->status));
> + return PTR_ERR(conf->status);
> + }
> +
> + return fpga_mgr_register(&spi->dev,
> + "Altera Cyclone PS SPI FPGA Manager",
> + &cyclonespi_ops, conf);
> +}
> +
> +static int cyclonespi_remove(struct spi_device *spi)
> +{
> + fpga_mgr_unregister(&spi->dev);
> +
> + return 0;
> +}
> +
> +static struct spi_driver cyclonespi_driver = {
> + .driver = {
> + .name = "cyclone-ps-spi",
> + .owner = THIS_MODULE,
> + .of_match_table = of_match_ptr(of_ef_match),
> + },
> + .probe = cyclonespi_probe,
> + .remove = cyclonespi_remove,
> +};
> +
> +module_spi_driver(cyclonespi_driver)
> +
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("Joshua Clayton <stillcompiling@xxxxxxxxx>");
> +MODULE_DESCRIPTION("Module to load Altera FPGA firmware over spi");
> --
> 2.9.3
>
>
Thanks,
Alan
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