Re: [PATCH V3 XRT Alveo 13/18] fpga: xrt: devctl platform driver

Lizhi Hou
2021-03-16T23:55:44Z

On 03/04/2021 05:39 AM, Tom Rix wrote:
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>
> On 2/17/21 10:40 PM, Lizhi Hou wrote:
>> Add devctl driver. devctl is a type of hardware function which only has
>> few registers to read or write. They are discovered by walking firmware
>> metadata. A platform device node will be created for them.
>>
>> Signed-off-by: Sonal Santan <sonal.santan@xilinx.com>
>> Signed-off-by: Max Zhen <max.zhen@xilinx.com>
>> Signed-off-by: Lizhi Hou <lizhih@xilinx.com>
>> ---
>> drivers/fpga/xrt/include/xleaf/devctl.h | 43 +++++
>> drivers/fpga/xrt/lib/xleaf/devctl.c | 206 ++++++++++++++++++++++++
>> 2 files changed, 249 insertions(+)
>> create mode 100644 drivers/fpga/xrt/include/xleaf/devctl.h
>> create mode 100644 drivers/fpga/xrt/lib/xleaf/devctl.c
>>
>> diff --git a/drivers/fpga/xrt/include/xleaf/devctl.h b/drivers/fpga/xrt/include/xleaf/devctl.h
>> new file mode 100644
>> index 000000000000..96a40e066f83
>> --- /dev/null
>> +++ b/drivers/fpga/xrt/include/xleaf/devctl.h
>> @@ -0,0 +1,43 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/*
>> + * Header file for XRT DEVCTL Leaf Driver
>> + *
>> + * Copyright (C) 2020-2021 Xilinx, Inc.
>> + *
>> + * Authors:
>> + * Lizhi Hou <Lizhi.Hou@xilinx.com>
>> + */
>> +
>> +#ifndef _XRT_DEVCTL_H_
>> +#define _XRT_DEVCTL_H_
>> +
>> +#include "xleaf.h"
>> +
>> +/*
>> + * DEVCTL driver IOCTL calls.
>> + */
>> +enum xrt_devctl_ioctl_cmd {
>> + XRT_DEVCTL_READ = XRT_XLEAF_CUSTOM_BASE, /* See comments in xleaf.h */
>> + XRT_DEVCTL_WRITE,
>> +};
>> +
>> +enum xrt_devctl_id {
>> + XRT_DEVCTL_ROM_UUID,
> Assumes 0, should make this explicit and initialize to 0
Sure.
>> + XRT_DEVCTL_DDR_CALIB,
>> + XRT_DEVCTL_GOLDEN_VER,
>> + XRT_DEVCTL_MAX
>> +};
>> +
>> +struct xrt_devctl_ioctl_rw {
>> + u32 xgir_id;
>> + void *xgir_buf;
>> + u32 xgir_len;
>> + u32 xgir_offset;
> similar to other patches, the xgir_ prefix is not needed
>> +};
>> +
>> +struct xrt_devctl_ioctl_intf_uuid {
>> + u32 xgir_uuid_num;
>> + uuid_t *xgir_uuids;
>> +};
>> +
>> +#endif /* _XRT_DEVCTL_H_ */
>> diff --git a/drivers/fpga/xrt/lib/xleaf/devctl.c b/drivers/fpga/xrt/lib/xleaf/devctl.c
>> new file mode 100644
>> index 000000000000..caf8c6569f0f
>> --- /dev/null
>> +++ b/drivers/fpga/xrt/lib/xleaf/devctl.c
>> @@ -0,0 +1,206 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Xilinx Alveo FPGA devctl Driver
>> + *
>> + * Copyright (C) 2020-2021 Xilinx, Inc.
>> + *
>> + * Authors:
>> + * Lizhi Hou<Lizhi.Hou@xilinx.com>
>> + */
>> +
>> +#include <linux/mod_devicetable.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/delay.h>
>> +#include <linux/device.h>
>> +#include <linux/io.h>
>> +#include "metadata.h"
>> +#include "xleaf.h"
>> +#include "xleaf/devctl.h"
>> +
>> +#define XRT_DEVCTL "xrt_devctl"
>> +
>> +struct xrt_name_id {
>> + char *ep_name;
>> + int id;
>> +};
>> +
>> +static struct xrt_name_id name_id[XRT_DEVCTL_MAX] = {
>> + { XRT_MD_NODE_BLP_ROM, XRT_DEVCTL_ROM_UUID },
>> + { XRT_MD_NODE_GOLDEN_VER, XRT_DEVCTL_GOLDEN_VER },
> DDR_CALIB is unused ?
Not sure if I understand the question correctly. ddr_calib will have
more things need to handle other than just read/write.
>> +};
>> +
>> +struct xrt_devctl {
>> + struct platform_device *pdev;
>> + void __iomem *base_addrs[XRT_DEVCTL_MAX];
>> + ulong sizes[XRT_DEVCTL_MAX];
>> +};
> similar to other patches, why not use regmap ?
Will change to regmap.
>> +
>> +static int xrt_devctl_name2id(struct xrt_devctl *devctl, const char *name)
>> +{
>> + int i;
>> +
>> + for (i = 0; i < XRT_DEVCTL_MAX && name_id[i].ep_name; i++) {
>> + if (!strncmp(name_id[i].ep_name, name, strlen(name_id[i].ep_name) + 1))
>> + return name_id[i].id;
>> + }
>> +
>> + return -EINVAL;
>> +}
>> +
>> +static int
>> +xrt_devctl_leaf_ioctl(struct platform_device *pdev, u32 cmd, void *arg)
>> +{
>> + struct xrt_devctl *devctl;
>> + int ret = 0;
>> +
>> + devctl = platform_get_drvdata(pdev);
>> +
>> + switch (cmd) {
>> + case XRT_XLEAF_EVENT:
>> + /* Does not handle any event. */
>> + break;
>> + case XRT_DEVCTL_READ: {
>> + struct xrt_devctl_ioctl_rw *rw_arg = arg;
>> + u32 *p_src, *p_dst, i;
>> +
>> + if (rw_arg->xgir_len & 0x3) {
>> + xrt_err(pdev, "invalid len %d", rw_arg->xgir_len);
>> + return -EINVAL;
>> + }
>> +
>> + if (rw_arg->xgir_id >= XRT_DEVCTL_MAX) {
>> + xrt_err(pdev, "invalid id %d", rw_arg->xgir_id);
>> + return -EINVAL;
>> + }
> needs a < 0 check ?
change xgir_id to u32.
>> +
>> + p_src = devctl->base_addrs[rw_arg->xgir_id];
>> + if (!p_src) {
>> + xrt_err(pdev, "io not found, id %d",
>> + rw_arg->xgir_id);
>> + return -EINVAL;
>> + }
>> + if (rw_arg->xgir_offset + rw_arg->xgir_len >
>> + devctl->sizes[rw_arg->xgir_id]) {
>> + xrt_err(pdev, "invalid argument, off %d, len %d",
>> + rw_arg->xgir_offset, rw_arg->xgir_len);
>> + return -EINVAL;
>> + }
>> + p_dst = rw_arg->xgir_buf;
>> + for (i = 0; i < rw_arg->xgir_len / sizeof(u32); i++) {
>> + u32 val = ioread32(p_src + rw_arg->xgir_offset + i);
>> +
>> + memcpy(p_dst + i, &val, sizeof(u32));
>> + }
>> + break;
>> + }
> The _WRITE msg is not handled Then why have it ?
Will remove write msg from this patch set and add it back in future patches.

Thanks,
Lizhi
>
> Tom
>
>> + default:
>> + xrt_err(pdev, "unsupported cmd %d", cmd);
>> + return -EINVAL;
>> + }
>> +
>> + return ret;
>> +}
>> +
>> +static int xrt_devctl_remove(struct platform_device *pdev)
>> +{
>> + struct xrt_devctl *devctl;
>> + int i;
>> +
>> + devctl = platform_get_drvdata(pdev);
>> +
>> + for (i = 0; i < XRT_DEVCTL_MAX; i++) {
>> + if (devctl->base_addrs[i])
>> + iounmap(devctl->base_addrs[i]);
>> + }
>> +
>> + platform_set_drvdata(pdev, NULL);
>> + devm_kfree(&pdev->dev, devctl);
>> +
>> + return 0;
>> +}
>> +
>> +static int xrt_devctl_probe(struct platform_device *pdev)
>> +{
>> + struct xrt_devctl *devctl;
>> + int i, id, ret = 0;
>> + struct resource *res;
>> +
>> + devctl = devm_kzalloc(&pdev->dev, sizeof(*devctl), GFP_KERNEL);
>> + if (!devctl)
>> + return -ENOMEM;
>> +
>> + devctl->pdev = pdev;
>> + platform_set_drvdata(pdev, devctl);
>> +
>> + xrt_info(pdev, "probing...");
>> + for (i = 0, res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> + res;
>> + res = platform_get_resource(pdev, IORESOURCE_MEM, ++i)) {
>> + id = xrt_devctl_name2id(devctl, res->name);
>> + if (id < 0) {
>> + xrt_err(pdev, "ep %s not found", res->name);
>> + continue;
>> + }
>> + devctl->base_addrs[id] = ioremap(res->start, res->end - res->start + 1);
>> + if (!devctl->base_addrs[id]) {
>> + xrt_err(pdev, "map base failed %pR", res);
>> + ret = -EIO;
>> + goto failed;
>> + }
>> + devctl->sizes[id] = res->end - res->start + 1;
>> + }
>> +
>> +failed:
>> + if (ret)
>> + xrt_devctl_remove(pdev);
>> +
>> + return ret;
>> +}
>> +
>> +static struct xrt_subdev_endpoints xrt_devctl_endpoints[] = {
>> + {
>> + .xse_names = (struct xrt_subdev_ep_names[]) {
>> + /* add name if ep is in same partition */
>> + { .ep_name = XRT_MD_NODE_BLP_ROM },
>> + { NULL },
>> + },
>> + .xse_min_ep = 1,
>> + },
>> + {
>> + .xse_names = (struct xrt_subdev_ep_names[]) {
>> + { .ep_name = XRT_MD_NODE_GOLDEN_VER },
>> + { NULL },
>> + },
>> + .xse_min_ep = 1,
>> + },
>> + /* adding ep bundle generates devctl device instance */
>> + { 0 },
>> +};
>> +
>> +static struct xrt_subdev_drvdata xrt_devctl_data = {
>> + .xsd_dev_ops = {
>> + .xsd_ioctl = xrt_devctl_leaf_ioctl,
>> + },
>> +};
>> +
>> +static const struct platform_device_id xrt_devctl_table[] = {
>> + { XRT_DEVCTL, (kernel_ulong_t)&xrt_devctl_data },
>> + { },
>> +};
>> +
>> +static struct platform_driver xrt_devctl_driver = {
>> + .driver = {
>> + .name = XRT_DEVCTL,
>> + },
>> + .probe = xrt_devctl_probe,
>> + .remove = xrt_devctl_remove,
>> + .id_table = xrt_devctl_table,
>> +};
>> +
>> +void devctl_leaf_init_fini(bool init)
>> +{
>> + if (init)
>> + xleaf_register_driver(XRT_SUBDEV_DEVCTL, &xrt_devctl_driver, xrt_devctl_endpoints);
>> + else
>> + xleaf_unregister_driver(XRT_SUBDEV_DEVCTL);
>> +}