Re: [PATCH v2] ufs: core: Add WB buffer resize support
From: Bean Huo
Date: Sat Oct 26 2024 - 15:40:44 EST
Hi Tang,
I saw that "Both UFS 4.1 and UFS 5.0 are currently in development" have
not been officially published yet. Are you keen to incorporate features
based on an unpublished standard?
Kind regards,
Bean
On Sat, 2024-10-26 at 08:44 +0800, Huan Tang wrote:
> Support WB buffer resize function through sysfs, the host can obtain
> resize hint and resize status and enable the resize operation. To
> achieve this goals, three sysfs nodes have been added:
> 1. wb_toggle_buf_resize
> 2. wb_buf_resize_hint
> 3. wb_buf_resize_status
>
> The detailed definition of the three nodes can be found in the sysfs
> documentation.
>
> Changelog
> ===
> v1 - > v2:
> remove unused variable "u8 index",
> drivers/ufs/core/ufs-sysfs.c:419:12: warning: variable
> 'index'
> set but not used.
>
> v1
>
> https://lore.kernel.org/all/20241025085924.4855-1-tanghuan@xxxxxxxx/
>
> Signed-off-by: Huan Tang <tanghuan@xxxxxxxx>
> Signed-off-by: Lu Hongfei <luhongfei@xxxxxxxx>
> ---
> Documentation/ABI/testing/sysfs-driver-ufs | 52
> ++++++++++++++++++++++
> drivers/ufs/core/ufs-sysfs.c | 43 ++++++++++++++++++
> drivers/ufs/core/ufshcd.c | 15 +++++++
> include/ufs/ufs.h | 5 ++-
> include/ufs/ufshcd.h | 1 +
> 5 files changed, 115 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/ABI/testing/sysfs-driver-ufs
> b/Documentation/ABI/testing/sysfs-driver-ufs
> index 5fa6655aee84..dbaa84277801 100644
> --- a/Documentation/ABI/testing/sysfs-driver-ufs
> +++ b/Documentation/ABI/testing/sysfs-driver-ufs
> @@ -1559,3 +1559,55 @@ Description:
> Symbol - HCMID. This file shows the UFSHCD
> manufacturer id.
> The Manufacturer ID is defined by JEDEC in JEDEC-
> JEP106.
> The file is read only.
> +
> +What: /sys/bus/platform/drivers/ufshcd/*/wb_toggle_buf_resi
> ze
> +What: /sys/bus/platform/devices/*.ufs/wb_toggle_buf_resize
> +Date: Qct 2024
> +Contact: Huan Tang <tanghuan@xxxxxxxx>
> +Description:
> + The host can decrease or increase the WriteBooster
> Buffer size by setting
> + this file.
> +
> + ====== ======================================
> + 00h Idle (There is no resize operation)
> + 01h Decrease WriteBooster Buffer Size
> + 02h Increase WriteBooster Buffer Size
> + Others Reserved
> + ====== ======================================
> +
> + The file is write only.
> +
> +What: /sys/bus/platform/drivers/ufshcd/*/attributes/wb_buf_
> resize_hint
> +What: /sys/bus/platform/devices/*.ufs/attributes/wb_buf_res
> ize_hint
> +Date: Qct 2024
> +Contact: Huan Tang <tanghuan@xxxxxxxx>
> +Description:
> + wb_buf_resize_hint indicates hint information about
> which type of resize for
> + WriteBooster Buffer is recommended by the device.
> +
> + ====== ======================================
> + 00h Recommend keep the buffer size
> + 01h Recommend to decrease the buffer size
> + 02h Recommend to increase the buffer size
> + Others: Reserved
> + ====== ======================================
> +
> + The file is read only.
> +
> +What: /sys/bus/platform/drivers/ufshcd/*/attributes/wb_buf_
> resize_status
> +What: /sys/bus/platform/devices/*.ufs/attributes/wb_buf_res
> ize_status
> +Date: Qct 2024
> +Contact: Huan Tang <tanghuan@xxxxxxxx>
> +Description:
> + The host can check the Resize operation status of the
> WriteBooster Buffer
> + by reading this file.
> +
> + ====== ========================================
> + 00h Idle (resize operation is not issued)
> + 01h Resize operation in progress
> + 02h Resize operation completed successfully
> + 03h Resize operation general failure
> + Others Reserved
> + ====== ========================================
> +
> + The file is read only.
> diff --git a/drivers/ufs/core/ufs-sysfs.c b/drivers/ufs/core/ufs-
> sysfs.c
> index 265f21133b63..bb21982394c8 100644
> --- a/drivers/ufs/core/ufs-sysfs.c
> +++ b/drivers/ufs/core/ufs-sysfs.c
> @@ -411,6 +411,43 @@ static ssize_t wb_flush_threshold_store(struct
> device *dev,
> return count;
> }
>
> +static ssize_t wb_toggle_buf_resize_store(struct device *dev,
> + struct device_attribute *attr, const char *buf,
> size_t count)
> +{
> + struct ufs_hba *hba = dev_get_drvdata(dev);
> + unsigned int wb_buf_resize_op;
> + ssize_t res;
> +
> + if (!ufshcd_is_wb_allowed(hba) || !hba->dev_info.wb_enabled
> ||
> + !hba->dev_info.b_presrv_uspc_en) {
> + dev_err(dev, "The WB buf resize is not allowed!\n");
> + return -EOPNOTSUPP;
> + }
> +
> + if (kstrtouint(buf, 0, &wb_buf_resize_op))
> + return -EINVAL;
> +
> + if (wb_buf_resize_op != 0x01 && wb_buf_resize_op != 0x02) {
> + dev_err(dev, "The operation %u is invalid!\n",
> wb_buf_resize_op);
> + return -EINVAL;
> + }
> +
> + down(&hba->host_sem);
> + if (!ufshcd_is_user_access_allowed(hba)) {
> + res = -EBUSY;
> + goto out;
> + }
> +
> + index = ufshcd_wb_get_query_index(hba);
> + ufshcd_rpm_get_sync(hba);
> + res = ufshcd_wb_toggle_buf_resize(hba, wb_buf_resize_op);
> + ufshcd_rpm_put_sync(hba);
> +
> +out:
> + up(&hba->host_sem);
> + return res < 0 ? res : count;
> +}
> +
> /**
> * pm_qos_enable_show - sysfs handler to show pm qos enable value
> * @dev: device associated with the UFS controller
> @@ -468,6 +505,7 @@ static DEVICE_ATTR_RW(auto_hibern8);
> static DEVICE_ATTR_RW(wb_on);
> static DEVICE_ATTR_RW(enable_wb_buf_flush);
> static DEVICE_ATTR_RW(wb_flush_threshold);
> +static DEVICE_ATTR_WO(wb_toggle_buf_resize);
> static DEVICE_ATTR_RW(rtc_update_ms);
> static DEVICE_ATTR_RW(pm_qos_enable);
>
> @@ -482,6 +520,7 @@ static struct attribute *ufs_sysfs_ufshcd_attrs[]
> = {
> &dev_attr_wb_on.attr,
> &dev_attr_enable_wb_buf_flush.attr,
> &dev_attr_wb_flush_threshold.attr,
> + &dev_attr_wb_toggle_buf_resize.attr,
> &dev_attr_rtc_update_ms.attr,
> &dev_attr_pm_qos_enable.attr,
> NULL
> @@ -1526,6 +1565,8 @@ UFS_ATTRIBUTE(wb_flush_status,
> _WB_FLUSH_STATUS);
> UFS_ATTRIBUTE(wb_avail_buf, _AVAIL_WB_BUFF_SIZE);
> UFS_ATTRIBUTE(wb_life_time_est, _WB_BUFF_LIFE_TIME_EST);
> UFS_ATTRIBUTE(wb_cur_buf, _CURR_WB_BUFF_SIZE);
> +UFS_ATTRIBUTE(wb_buf_resize_hint, _WB_BUF_RESIZE_HINT);
> +UFS_ATTRIBUTE(wb_buf_resize_status, _WB_BUF_RESIZE_STATUS);
>
>
> static struct attribute *ufs_sysfs_attributes[] = {
> @@ -1549,6 +1590,8 @@ static struct attribute *ufs_sysfs_attributes[]
> = {
> &dev_attr_wb_avail_buf.attr,
> &dev_attr_wb_life_time_est.attr,
> &dev_attr_wb_cur_buf.attr,
> + &dev_attr_wb_buf_resize_hint.attr,
> + &dev_attr_wb_buf_resize_status.attr,
> NULL,
> };
>
> diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
> index 630409187c10..c28915debab6 100644
> --- a/drivers/ufs/core/ufshcd.c
> +++ b/drivers/ufs/core/ufshcd.c
> @@ -6167,6 +6167,21 @@ static bool ufshcd_wb_need_flush(struct
> ufs_hba *hba)
> return ufshcd_wb_presrv_usrspc_keep_vcc_on(hba, avail_buf);
> }
>
> +int ufshcd_wb_toggle_buf_resize(struct ufs_hba *hba, u32 op)
> +{
> + int ret;
> + u8 index;
> +
> + index = ufshcd_wb_get_query_index(hba);
> + ret = ufshcd_query_attr_retry(hba,
> UPIU_QUERY_OPCODE_WRITE_ATTR,
> + QUERY_ATTR_IDN_WB_BUF_RESIZE_EN,
> index, 0, &op);
> + if (ret)
> + dev_err(hba->dev, "%s: Enable WB buf resize operation
> failed %d\n",
> + __func__, ret);
> +
> + return ret;
> +}
> +
> static void ufshcd_rpm_dev_flush_recheck_work(struct work_struct
> *work)
> {
> struct ufs_hba *hba = container_of(to_delayed_work(work),
> diff --git a/include/ufs/ufs.h b/include/ufs/ufs.h
> index e594abe5d05f..f737d98044ac 100644
> --- a/include/ufs/ufs.h
> +++ b/include/ufs/ufs.h
> @@ -181,7 +181,10 @@ enum attr_idn {
> QUERY_ATTR_IDN_WB_BUFF_LIFE_TIME_EST = 0x1E,
> QUERY_ATTR_IDN_CURR_WB_BUFF_SIZE = 0x1F,
> QUERY_ATTR_IDN_EXT_IID_EN = 0x2A,
> - QUERY_ATTR_IDN_TIMESTAMP = 0x30
> + QUERY_ATTR_IDN_TIMESTAMP = 0x30,
> + QUERY_ATTR_IDN_WB_BUF_RESIZE_HINT = 0x3C,
> + QUERY_ATTR_IDN_WB_BUF_RESIZE_EN = 0x3D,
> + QUERY_ATTR_IDN_WB_BUF_RESIZE_STATUS = 0x3E,
> };
>
> /* Descriptor idn for Query requests */
> diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h
> index a95282b9f743..cbe208ce9293 100644
> --- a/include/ufs/ufshcd.h
> +++ b/include/ufs/ufshcd.h
> @@ -1454,6 +1454,7 @@ int ufshcd_advanced_rpmb_req_handler(struct
> ufs_hba *hba, struct utp_upiu_req *r
> struct scatterlist *sg_list,
> enum dma_data_direction dir);
> int ufshcd_wb_toggle(struct ufs_hba *hba, bool enable);
> int ufshcd_wb_toggle_buf_flush(struct ufs_hba *hba, bool enable);
> +int ufshcd_wb_toggle_buf_resize(struct ufs_hba *hba, u32 op);
> int ufshcd_suspend_prepare(struct device *dev);
> int __ufshcd_suspend_prepare(struct device *dev, bool
> rpm_ok_for_spm);
> void ufshcd_resume_complete(struct device *dev);