On Mar 3, 2024, at 12:22 PM, Charles Perry charles.perry@xxxxxxxxxxxxxxxxxxxx wrote:
> On Feb 26, 2024, at 2:50 AM, Xu Yilun yilun.xu@xxxxxxxxxxxxxxx wrote:
>
>> On Wed, Feb 21, 2024 at 02:50:49PM -0500, 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>
>>> ---
>>> drivers/fpga/Kconfig | 8 +++
>>> drivers/fpga/Makefile | 1 +
>>> drivers/fpga/xilinx-selectmap.c | 97 +++++++++++++++++++++++++++++++++
>>> 3 files changed, 106 insertions(+)
>>> 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-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>
>>> +
>>> +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;
>>> +
>>> + 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);
>>> + 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);
>>
>> Does the driver have to be used with OF or not?
>>
>> If yes, please specify the reason and enforce in Kconfig.
>> If no, please ensure it decently compiles without CONFIG_OF.
>>
>> Thanks,
>> Yilun
>>
>
> No, it doesn't need OF explicitly as it only needs a few GPIO and a
> memory mapped IO region. It would be possible to get this info from
> platform data.
>
> I'll fix the compilation without CONFIG_OF.
It does compile without CONFIG_OF in its current form as I can compile
it for x86_64 without warnings.
One of the reason why xilinx-spi.c needs an "#ifdef CONFIG_OF" wrapper
around the of_device_id table is because it uses of_match_ptr() which
resolves to NULL when CONFIG_OF is not set, which triggers an unused
variable warning. This is not the case in xilinx-selectmap.c because
it's not using of_match_ptr().
Regards,
Charles
>
> Regards,
> Charles
>
>>> +
>>> +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
