Re: [PATCH V3 XRT Alveo 13/18] fpga: xrt: devctl platform driver
From: Tom Rix
Date: Wed Mar 17 2021 - 17:17:27 EST
On 3/16/21 4:54 PM, Lizhi Hou wrote:
>
>
> On 03/04/2021 05:39 AM, Tom Rix wrote:
>> CAUTION: This message has originated from an External Source. Please use proper judgment and caution when opening attachments, clicking links, or responding to this email.
>>
>>
>> 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@xxxxxxxxxx>
>>> Signed-off-by: Max Zhen <max.zhen@xxxxxxxxxx>
>>> Signed-off-by: Lizhi Hou <lizhih@xxxxxxxxxx>
>>> ---
>>> 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@xxxxxxxxxx>
>>> + */
>>> +
>>> +#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@xxxxxxxxxx>
>>> + */
>>> +
>>> +#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.
I do not understand either, ignore this comment.
If it is important, I will bring it up in a later revision's review and do a better job of explaining the issue.
Tom
>>> +};
>>> +
>>> +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);
>>> +}
>