Re: [PATCH v4 14/16] scsi: ufs: ufs-exynos: multi-host configuration for exynosauto

[Inki Dae <inki.dae@samsung.com>]

21. 10. 7. 오후 5:09에 Chanho Park 이(가) 쓴 글:
> UFS controller of ExynosAuto v9 SoC supports multi-host interface for I/O
> virtualization. In general, we're using para-virtualized driver to
> support a block device by several virtual machines. However, it should
> be relayed by backend driver. Multi-host functionality extends the host
> controller by providing register interfaces that can be used by each
> VM's ufs drivers respectively. By this, we can provide direct access to
> the UFS device for multiple VMs. It's similar with SR-IOV of PCIe.
> 
> We divide this M-HCI as PH(Physical Host) and VHs(Virtual Host). The PH
> supports all UFSHCI functions(all SAPs) same as conventional UFSHCI but
> the VH only supports data transfer function. Thus, except UTP_CMD_SAP and
> UTP_TMPSAP, the PH should handle all the physical features.
> 
> This patch provides an initial implementation of PH part. M-HCI can
> support up to four interfaces but this patch initially supports only 1
> PH and 1 VH. For this, we uses TASK_TAG[7:5] field so TASK_TAG[4:0] for
> 32 doorbel will be supported. After the PH is initiated, this will send
> a ready message to VHs through a mailbox register. The message handler
> is not fully implemented yet such as supporting reset / abort cases.
> 
> Cc: Alim Akhtar <alim.akhtar@samsung.com>
> Cc: Kiwoong Kim <kwmad.kim@samsung.com>
> Cc: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
> Cc: Inki Dae <inki.dae@samsung.com>
> Signed-off-by: Chanho Park <chanho61.park@samsung.com>
> ---
>  drivers/scsi/ufs/ufs-exynos.c | 68 +++++++++++++++++++++++++++++++++++
>  1 file changed, 68 insertions(+)
> 
> diff --git a/drivers/scsi/ufs/ufs-exynos.c b/drivers/scsi/ufs/ufs-exynos.c
> index 9d32f19395b8..32f73c906018 100644
> --- a/drivers/scsi/ufs/ufs-exynos.c
> +++ b/drivers/scsi/ufs/ufs-exynos.c
> @@ -83,6 +83,44 @@
>  #define UFS_SHARABLE		(UFS_WR_SHARABLE | UFS_RD_SHARABLE)
>  #define UFS_SHAREABILITY_OFFSET	0x710
>  
> +/* Multi-host registers */
> +#define MHCTRL			0xC4
> +#define MHCTRL_EN_VH_MASK	(0xE)
> +#define MHCTRL_EN_VH(vh)	(vh << 1)
> +#define PH2VH_MBOX		0xD8
> +
> +#define MH_MSG_MASK		(0xFF)
> +
> +#define MH_MSG(id, msg)		((id << 8) | (msg & 0xFF))
> +#define MH_MSG_PH_READY		0x1
> +#define MH_MSG_VH_READY		0x2
> +
> +#define ALLOW_INQUIRY		BIT(25)
> +#define ALLOW_MODE_SELECT	BIT(24)
> +#define ALLOW_MODE_SENSE	BIT(23)
> +#define ALLOW_PRE_FETCH		GENMASK(22, 21)
> +#define ALLOW_READ_CMD_ALL	GENMASK(20, 18)	/* read_6/10/16 */
> +#define ALLOW_READ_BUFFER	BIT(17)
> +#define ALLOW_READ_CAPACITY	GENMASK(16, 15)
> +#define ALLOW_REPORT_LUNS	BIT(14)
> +#define ALLOW_REQUEST_SENSE	BIT(13)
> +#define ALLOW_SYNCHRONIZE_CACHE	GENMASK(8, 7)
> +#define ALLOW_TEST_UNIT_READY	BIT(6)
> +#define ALLOW_UNMAP		BIT(5)
> +#define ALLOW_VERIFY		BIT(4)
> +#define ALLOW_WRITE_CMD_ALL	GENMASK(3, 1)	/* write_6/10/16 */
> +
> +#define ALLOW_TRANS_VH_DEFAULT	(ALLOW_INQUIRY | ALLOW_MODE_SELECT | \
> +				 ALLOW_MODE_SENSE | ALLOW_PRE_FETCH | \
> +				 ALLOW_READ_CMD_ALL | ALLOW_READ_BUFFER | \
> +				 ALLOW_READ_CAPACITY | ALLOW_REPORT_LUNS | \
> +				 ALLOW_REQUEST_SENSE | ALLOW_SYNCHRONIZE_CACHE | \
> +				 ALLOW_TEST_UNIT_READY | ALLOW_UNMAP | \
> +				 ALLOW_VERIFY | ALLOW_WRITE_CMD_ALL)
> +
> +#define HCI_MH_ALLOWABLE_TRAN_OF_VH		0x30C
> +#define HCI_MH_IID_IN_TASK_TAG			0X308
> +
>  enum {
>  	UNIPRO_L1_5 = 0,/* PHY Adapter */
>  	UNIPRO_L2,	/* Data Link */
> @@ -174,6 +212,20 @@ static int exynosauto_ufs_drv_init(struct device *dev, struct exynos_ufs *ufs)
>  	return 0;
>  }
>  
> +static int exynosauto_ufs_post_hce_enable(struct exynos_ufs *ufs)
> +{
> +	struct ufs_hba *hba = ufs->hba;
> +
> +	/* Enable Virtual Host #1 */
> +	ufshcd_rmwl(hba, MHCTRL_EN_VH_MASK, MHCTRL_EN_VH(1), MHCTRL);
> +	/* Default VH Transfer permissions */
> +	hci_writel(ufs, ALLOW_TRANS_VH_DEFAULT, HCI_MH_ALLOWABLE_TRAN_OF_VH);
> +	/* IID information is replaced in TASKTAG[7:5] instead of IID in UCD */
> +	hci_writel(ufs, 0x1, HCI_MH_IID_IN_TASK_TAG);
> +

Reviewed-by : Inki Dae <inki.dae@samsung.com>

Thanks,
Inki Dae