On Mar 19, 2024, at 2:35 AM, Xu Yilun yilun.xu@xxxxxxxxxxxxxxx wrote:
> On Wed, Mar 13, 2024 at 06:57:37PM -0400, Charles Perry wrote:
>> Xilinx 7 series FPGA can be programmed using a parallel port named
>> the SelectMAP interface in the datasheet. This interface is compatible
>> with the i.MX6 EIM bus controller but other types of external memory
>> mapped parallel bus might work.
>>
>> xilinx-selectmap currently only supports the x8 mode where data is loaded
>> at one byte per rising edge of the clock, with the MSb of each byte
>> presented to the D0 pin.
>>
>> Signed-off-by: Charles Perry <charles.perry@xxxxxxxxxxxxxxxxxxxx>
>> ---
>> Changes since v4: (from Yilun review)
>> * xilinx-core: select between prog/init and prog_b/init-b
>>
>> drivers/fpga/Kconfig | 8 +++
>> drivers/fpga/Makefile | 1 +
>> drivers/fpga/xilinx-core.c | 29 +++++++++-
>> drivers/fpga/xilinx-selectmap.c | 97 +++++++++++++++++++++++++++++++++
>> 4 files changed, 133 insertions(+), 2 deletions(-)
>> create mode 100644 drivers/fpga/xilinx-selectmap.c
>>
>> diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
>> index d27a1ebf40838..37b35f58f0dfb 100644
>> --- a/drivers/fpga/Kconfig
>> +++ b/drivers/fpga/Kconfig
>> @@ -67,6 +67,14 @@ config FPGA_MGR_STRATIX10_SOC
>> config FPGA_MGR_XILINX_CORE
>> tristate
>>
>> +config FPGA_MGR_XILINX_SELECTMAP
>> + tristate "Xilinx Configuration over SelectMAP"
>> + depends on HAS_IOMEM
>> + select FPGA_MGR_XILINX_CORE
>> + help
>> + FPGA manager driver support for Xilinx FPGA configuration
>> + over SelectMAP interface.
>> +
>> config FPGA_MGR_XILINX_SPI
>> tristate "Xilinx Configuration over Slave Serial (SPI)"
>> depends on SPI
>> diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
>> index 7ec795b6a5a70..aeb89bb13517e 100644
>> --- a/drivers/fpga/Makefile
>> +++ b/drivers/fpga/Makefile
>> @@ -16,6 +16,7 @@ obj-$(CONFIG_FPGA_MGR_SOCFPGA_A10) += socfpga-a10.o
>> obj-$(CONFIG_FPGA_MGR_STRATIX10_SOC) += stratix10-soc.o
>> obj-$(CONFIG_FPGA_MGR_TS73XX) += ts73xx-fpga.o
>> obj-$(CONFIG_FPGA_MGR_XILINX_CORE) += xilinx-core.o
>> +obj-$(CONFIG_FPGA_MGR_XILINX_SELECTMAP) += xilinx-selectmap.o
>> obj-$(CONFIG_FPGA_MGR_XILINX_SPI) += xilinx-spi.o
>> obj-$(CONFIG_FPGA_MGR_ZYNQ_FPGA) += zynq-fpga.o
>> obj-$(CONFIG_FPGA_MGR_ZYNQMP_FPGA) += zynqmp-fpga.o
>> diff --git a/drivers/fpga/xilinx-core.c b/drivers/fpga/xilinx-core.c
>> index a35c43382dd5f..ccdeb45eba4ee 100644
>> --- a/drivers/fpga/xilinx-core.c
>> +++ b/drivers/fpga/xilinx-core.c
>> @@ -171,6 +171,29 @@ static int xilinx_core_write_complete(struct fpga_manager
>> *mgr,
>> return -ETIMEDOUT;
>> }
>>
>> +/**
>> + * xilinx_core_devm_gpiod_get - Obtain a resource-managed GPIO using a
>> + * legacy consumer name fallback.
>> + *
>> + * @dev: Device managing the GPIO
>> + * @con_id: Consumer id
>> + * @legacy_con_id: Legacy consumer id
>> + * @flags: optional GPIO initialization flags
>> + */
>
> No need to have kernel doc comments for internal functions.
>
Ok, will remove.
>> +static inline struct gpio_desc *
>> +xilinx_core_devm_gpiod_get(struct device *dev, const char *con_id,
>> + const char *legacy_con_id, enum gpiod_flags flags)
>> +{
>> + struct gpio_desc *desc;
>> +
>> + desc = devm_gpiod_get(dev, con_id, flags);
>> + if (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT &&
>> + of_device_is_compatible(dev->of_node, "xlnx,fpga-slave-serial"))
>> + desc = devm_gpiod_get(dev, legacy_con_id, flags);
>> +
>> + return desc;
>> +}
>> +
>> static const struct fpga_manager_ops xilinx_core_ops = {
>> .state = xilinx_core_state,
>> .write_init = xilinx_core_write_init,
>> @@ -186,12 +209,14 @@ int xilinx_core_probe(struct xilinx_fpga_core *core)
>> return -EINVAL;
>>
>> /* PROGRAM_B is active low */
>> - core->prog_b = devm_gpiod_get(core->dev, "prog_b", GPIOD_OUT_LOW);
>> + core->prog_b = xilinx_core_devm_gpiod_get(core->dev, "prog", "prog_b",
>> + GPIOD_OUT_LOW);
>> if (IS_ERR(core->prog_b))
>> return dev_err_probe(core->dev, PTR_ERR(core->prog_b),
>> "Failed to get PROGRAM_B gpio\n");
>>
>> - core->init_b = devm_gpiod_get_optional(core->dev, "init-b", GPIOD_IN);
>> + core->init_b = xilinx_core_devm_gpiod_get(core->dev, "init", "init-b",
>> + GPIOD_IN);
>> if (IS_ERR(core->init_b))
>> return dev_err_probe(core->dev, PTR_ERR(core->init_b),
>> "Failed to get INIT_B gpio\n");
>
> Please make a separate patch for the naming change. This give a chance
> to explain why the change and how to correctly use the GPIO names.
>
Ok
>> diff --git a/drivers/fpga/xilinx-selectmap.c b/drivers/fpga/xilinx-selectmap.c
>> new file mode 100644
>> index 0000000000000..b63f4623f8b2c
>> --- /dev/null
>> +++ b/drivers/fpga/xilinx-selectmap.c
>> @@ -0,0 +1,97 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +/*
>> + * Xilinx Spartan6 and 7 Series SelectMAP interface driver
>> + *
>> + * (C) 2024 Charles Perry <charles.perry@xxxxxxxxxxxxxxxxxxxx>
>> + *
>> + * Manage Xilinx FPGA firmware loaded over the SelectMAP configuration
>> + * interface.
>> + */
>> +
>> +#include "xilinx-core.h"
>> +
>> +#include <linux/platform_device.h>
>> +#include <linux/gpio/consumer.h>
>> +#include <linux/module.h>
>> +#include <linux/mod_devicetable.h>
>> +#include <linux/of.h>
>> +#include <linux/io.h>
>
> alphabetical order please.
>
Ok
>> +
>> +struct xilinx_selectmap_conf {
>> + struct xilinx_fpga_core core;
>> + void __iomem *base;
>> +};
>> +
>> +#define to_xilinx_selectmap_conf(obj) \
>> + container_of(obj, struct xilinx_selectmap_conf, core)
>> +
>> +static int xilinx_selectmap_write(struct xilinx_fpga_core *core,
>> + const char *buf, size_t count)
>> +{
>> + struct xilinx_selectmap_conf *conf = to_xilinx_selectmap_conf(core);
>> + u32 i;
>> +
>> + for (i = 0; i < count; ++i)
>> + writeb(buf[i], conf->base);
>> +
>> + return 0;
>> +}
>> +
>> +static int xilinx_selectmap_probe(struct platform_device *pdev)
>> +{
>> + struct xilinx_selectmap_conf *conf;
>> + struct resource *r;
>> + void __iomem *base;
>> + struct gpio_desc *csi_b;
>> + struct gpio_desc *rdwr_b;
>
> One gpio_desc is enough, is it? We don't use these gpio_desc anywhere
> else.
>
Ok
> BTW, reverse Xmas tree is not strictly required, but please do it when it is
> easy to follow.
>
Ok
>> +
>> + conf = devm_kzalloc(&pdev->dev, sizeof(*conf), GFP_KERNEL);
>> + if (!conf)
>> + return -ENOMEM;
>> +
>> + conf->core.dev = &pdev->dev;
>> + conf->core.write = xilinx_selectmap_write;
>> +
>> + base = devm_platform_get_and_ioremap_resource(pdev, 0, &r);
>
> I can't find where 'r' is used.
>
> Thanks,
> Yilun
>
I'm guilty of keeping things around in case I need them in the future
here! Ok, will use NULL.
Regards,
Charles
>> + if (IS_ERR(base))
>> + return dev_err_probe(&pdev->dev, PTR_ERR(base),
>> + "ioremap error\n");
>> + conf->base = base;
>> +
>> + /* CSI_B is active low */
>> + csi_b = devm_gpiod_get_optional(&pdev->dev, "csi", GPIOD_OUT_HIGH);
>> + if (IS_ERR(csi_b))
>> + return dev_err_probe(&pdev->dev, PTR_ERR(csi_b),
>> + "Failed to get CSI_B gpio\n");
>> +
>> + /* RDWR_B is active low */
>> + rdwr_b = devm_gpiod_get_optional(&pdev->dev, "rdwr", GPIOD_OUT_HIGH);
>> + if (IS_ERR(rdwr_b))
>> + return dev_err_probe(&pdev->dev, PTR_ERR(rdwr_b),
>> + "Failed to get RDWR_B gpio\n");
>> +
>> + return xilinx_core_probe(&conf->core);
>> +}
>> +
>> +static const struct of_device_id xlnx_selectmap_of_match[] = {
>> + { .compatible = "xlnx,fpga-xc7s-selectmap", }, // Spartan-7
>> + { .compatible = "xlnx,fpga-xc7a-selectmap", }, // Artix-7
>> + { .compatible = "xlnx,fpga-xc7k-selectmap", }, // Kintex-7
>> + { .compatible = "xlnx,fpga-xc7v-selectmap", }, // Virtex-7
>> + {},
>> +};
>> +MODULE_DEVICE_TABLE(of, xlnx_selectmap_of_match);
>> +
>> +static struct platform_driver xilinx_selectmap_driver = {
>> + .driver = {
>> + .name = "xilinx-selectmap",
>> + .of_match_table = xlnx_selectmap_of_match,
>> + },
>> + .probe = xilinx_selectmap_probe,
>> +};
>> +
>> +module_platform_driver(xilinx_selectmap_driver);
>> +
>> +MODULE_LICENSE("GPL");
>> +MODULE_AUTHOR("Charles Perry <charles.perry@xxxxxxxxxxxxxxxxxxxx>");
>> +MODULE_DESCRIPTION("Load Xilinx FPGA firmware over SelectMap");
>> --
>> 2.43.0
