Re: [PATCH v6 2/5] hisi_acc_vfio_pci: modify the register location of the XQC address

From: Alex Williamson
Date: Fri May 03 2024 - 12:11:56 EST


On Thu, 25 Apr 2024 21:23:19 +0800
Longfang Liu <liulongfang@xxxxxxxxxx> wrote:

> According to the latest hardware register specification. The DMA
> addresses of EQE and AEQE are not at the front of their respective
> register groups, but start from the second.
> So, previously fetching the value starting from the first register
> would result in an incorrect address.
>
> Therefore, the register location from which the address is obtained
> needs to be modified.

How does this affect migration? Has it ever worked? Does this make
the migration data incompatible?

Fixes: ???

> Signed-off-by: Longfang Liu <liulongfang@xxxxxxxxxx>
> ---
> drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c | 8 ++++----
> drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h | 3 +++
> 2 files changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
> index 45351be8e270..0c7e31076ff4 100644
> --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
> +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
> @@ -516,12 +516,12 @@ static int vf_qm_state_save(struct hisi_acc_vf_core_device *hisi_acc_vdev,
> return -EINVAL;
>
> /* Every reg is 32 bit, the dma address is 64 bit. */
> - vf_data->eqe_dma = vf_data->qm_eqc_dw[1];
> + vf_data->eqe_dma = vf_data->qm_eqc_dw[QM_XQC_ADDR_HIGH];
> vf_data->eqe_dma <<= QM_XQC_ADDR_OFFSET;
> - vf_data->eqe_dma |= vf_data->qm_eqc_dw[0];
> - vf_data->aeqe_dma = vf_data->qm_aeqc_dw[1];
> + vf_data->eqe_dma |= vf_data->qm_eqc_dw[QM_XQC_ADDR_LOW];
> + vf_data->aeqe_dma = vf_data->qm_aeqc_dw[QM_XQC_ADDR_HIGH];
> vf_data->aeqe_dma <<= QM_XQC_ADDR_OFFSET;
> - vf_data->aeqe_dma |= vf_data->qm_aeqc_dw[0];
> + vf_data->aeqe_dma |= vf_data->qm_aeqc_dw[QM_XQC_ADDR_LOW];
>
> /* Through SQC_BT/CQC_BT to get sqc and cqc address */
> ret = qm_get_sqc(vf_qm, &vf_data->sqc_dma);
> diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
> index 5bab46602fad..f887ab98581c 100644
> --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
> +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
> @@ -38,6 +38,9 @@
> #define QM_REG_ADDR_OFFSET 0x0004
>
> #define QM_XQC_ADDR_OFFSET 32U
> +#define QM_XQC_ADDR_LOW 0x1
> +#define QM_XQC_ADDR_HIGH 0x2
> +
> #define QM_VF_AEQ_INT_MASK 0x0004
> #define QM_VF_EQ_INT_MASK 0x000c
> #define QM_IFC_INT_SOURCE_V 0x0020