[Skiboot] [PATCH v2] npu2: Fix npu2_{read,write}_4b()

[Alistair Popple]

Looks good! Thanks.

Acked-by: Alistair Popple <alistair at popple.id.au>

On Fri, 2 Jun 2017 09:52:51 AM Reza Arbab wrote:
> When writing or reading 4-byte values, we need to use the upper half of
> the 64-bit SCOM register.
> 
> Fix npu2_{read,write}_4b() and their callers to use uint32_t, and
> appropriately shift the value being written or returned.
> 
> Signed-off-by: Reza Arbab <arbab at linux.vnet.ibm.com>
> ---
> v2: Rebased on master branch. Oops!
> 
>  hw/npu2-hw-procedures.c |  4 ++--
>  hw/npu2.c               | 10 ++++++----
>  include/npu2.h          |  4 ++--
>  3 files changed, 10 insertions(+), 8 deletions(-)
> 
> diff --git a/hw/npu2-hw-procedures.c b/hw/npu2-hw-procedures.c
> index ade898e..6824179 100644
> --- a/hw/npu2-hw-procedures.c
> +++ b/hw/npu2-hw-procedures.c
> @@ -204,11 +204,11 @@ static uint32_t reset_ndl(struct npu2_dev *ndev)
>  
>  	npu2_write_mask(ndev->npu, NPU2_NTL_PRI_CFG(ndev), val, -1ULL);
>  
> -	val = PPC_BIT(0) | PPC_BIT(1);
> +	val = PPC_BIT32(0) | PPC_BIT32(1);
>  
>  	npu2_write_4b(ndev->npu, NPU2_NTL_DL_CONTROL(ndev), val);
>  	npu2_write_4b(ndev->npu, NPU2_NTL_DL_CONTROL(ndev), 0);
> -	npu2_write_4b(ndev->npu, NPU2_NTL_DL_CONFIG(ndev), PPC_BIT(0));
> +	npu2_write_4b(ndev->npu, NPU2_NTL_DL_CONFIG(ndev), PPC_BIT32(0));
>  
>  	/* NTL Reset */
>  	val = PPC_BIT(8) | PPC_BIT(9);
> diff --git a/hw/npu2.c b/hw/npu2.c
> index dc1a238..767666e 100644
> --- a/hw/npu2.c
> +++ b/hw/npu2.c
> @@ -87,14 +87,16 @@ static uint64_t npu2_scom_read(uint64_t gcid, uint64_t scom_base,
>  	return val;
>  }
>  
> -void npu2_write_4b(struct npu2 *p, uint64_t reg, uint64_t val)
> +void npu2_write_4b(struct npu2 *p, uint64_t reg, uint32_t val)
>  {
> -	npu2_scom_write(p->chip_id, p->xscom_base, reg, NPU2_MISC_DA_LEN_4B, val);
> +	npu2_scom_write(p->chip_id, p->xscom_base, reg, NPU2_MISC_DA_LEN_4B,
> +			(uint64_t)val << 32);
>  }
>  
> -uint64_t npu2_read_4b(struct npu2 *p, uint64_t reg)
> +uint32_t npu2_read_4b(struct npu2 *p, uint64_t reg)
>  {
> -	return npu2_scom_read(p->chip_id, p->xscom_base, reg, NPU2_MISC_DA_LEN_4B);
> +	return npu2_scom_read(p->chip_id, p->xscom_base, reg,
> +			      NPU2_MISC_DA_LEN_4B) >> 32;
>  }
>  
>  void npu2_write(struct npu2 *p, uint64_t reg, uint64_t val)
> diff --git a/include/npu2.h b/include/npu2.h
> index d15b2c9..6476c72 100644
> --- a/include/npu2.h
> +++ b/include/npu2.h
> @@ -139,8 +139,8 @@ static inline struct npu2 *phb_to_npu2(struct phb *phb)
>  	return container_of(phb, struct npu2, phb);
>  }
>  
> -void npu2_write_4b(struct npu2 *p, uint64_t reg, uint64_t val);
> -uint64_t npu2_read_4b(struct npu2 *p, uint64_t reg);
> +void npu2_write_4b(struct npu2 *p, uint64_t reg, uint32_t val);
> +uint32_t npu2_read_4b(struct npu2 *p, uint64_t reg);
>  void npu2_write(struct npu2 *p, uint64_t reg, uint64_t val);
>  uint64_t npu2_read(struct npu2 *p, uint64_t reg);
>  void npu2_write_mask(struct npu2 *p, uint64_t reg, uint64_t val, uint64_t mask);
>