On 7/19/22 04:15, Avri Altman wrote:
From: Eric Biggers <ebiggers@xxxxxxxxxx>
+config SCSI_UFS_VARIABLE_SG_ENTRY_SIZE
+ bool "Variable size UTP physical region descriptor"
+ help
+ In the UFSHCI 3.0 standard the Physical Region Descriptor (PRD) is a
+ data structure used for transferring data between host and UFS
+ device. This data structure describes a single region in physical
+ memory. Although the standard requires that this data structure has a
+ size of 16 bytes, for some controllers this data structure has a
+ different size. Enable this option for UFS controllers that need it.
Then this change should take the form of a quirk, AKA "opts" in exynos_ufs_drv_data.
Hi Avri,
I prefer a new CONFIG variable in combination with the
ufshcd_set_sg_entry_size() function because:
* Without the new CONFIG variable, the hot path would become slightly
slower for controllers that comply with the UFSHCI standard.
* I prefer to keep the details of the Exynos Physical Region Descriptor
in the Exynos driver instead of in the UFSHCI core.
Thanks,
Bart.
