Re: [PATCH v2 2/2] crypto: caam - allow retrieving 'era' from register

2018-04-11 Thread Fabio Estevam
Hi Horia,

On Wed, Apr 11, 2018 at 4:47 AM, Horia Geantă  wrote:

> Have you actually hit a case where the property was missing from DT?

Yes, on imx7s.dtsi it is missing.

I also started adding CAAM support to mx6ul and I did not pass the
""fsl,sec-era"

Thanks for your review.

I addressed all of your comments and sent a v3.


Re: [PATCH v2 2/2] crypto: caam - allow retrieving 'era' from register

2018-04-11 Thread Horia Geantă
On 4/11/2018 4:54 AM, Fabio Estevam wrote:
> From: Fabio Estevam 
> 
> The 'era' information can be retrieved from CAAM registers, so
> introduce a caam_get_era_from_hw() function that gets it via register
> reads in case the 'fsl,sec-era' property is not passed in the device
> tree.
> 
Indeed, "fsl,sec-era" property is marked as optional in DT bindings doc.
This means the previous commit
883619a931e9 ("crypto: caam - fix ERA retrieval function")
should have kept the detection based on registers as a fallback.

Have you actually hit a case where the property was missing from DT?

> This function is based on the U-Boot implementation from
> drivers/crypto/fsl/sec.c
> 
> Signed-off-by: Fabio Estevam 
> ---
> Changes since v1:
> - None. I previously asked to put the linux-crypto list on Cc
> 
>  drivers/crypto/caam/ctrl.c | 45 ++---
>  drivers/crypto/caam/regs.h |  6 ++
>  2 files changed, 48 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/crypto/caam/ctrl.c b/drivers/crypto/caam/ctrl.c
> index bee690a..3f10791 100644
> --- a/drivers/crypto/caam/ctrl.c
> +++ b/drivers/crypto/caam/ctrl.c
> @@ -396,11 +396,47 @@ static void kick_trng(struct platform_device *pdev, int 
> ent_delay)
>   clrsetbits_32(&r4tst->rtmctl, RTMCTL_PRGM, RTMCTL_SAMP_MODE_RAW_ES_SC);
>  }
>  
> +static u8 caam_get_era_from_hw(struct caam_ctrl __iomem *ctrl)
> +{
> + const struct sec_vid id[] = {
Make the struct static.

sec_vid should not be used since:
-it defines the layout of SECVID_MS register (ip_id, maj_rev, min_rev)
-while the array below contains (ip_id, maj_rev, era) tuples
You could instead use an anonymous struct, just like in kernel commit
82c2f9607b8a4 or as in u-boot.

> + {0x0A10, 1, 1},
> + {0x0A10, 2, 2},
> + {0x0A12, 1, 3},
> + {0x0A14, 1, 3},
> + {0x0A14, 2, 4},
> + {0x0A16, 1, 4},
> + {0x0A10, 3, 4},
> + {0x0A11, 1, 4},
> + {0x0A18, 1, 4},
> + {0x0A11, 2, 5},
> + {0x0A12, 2, 5},
> + {0x0A13, 1, 5},
> + {0x0A1C, 1, 5},
> + };
> + int i;
> +
> + u32 secvid_ms = rd_reg32(&ctrl->perfmon.caam_id_ms);
Reading caam_id_ms should be done only if ccbvid does not provide the era, i.e.
should be moved just before the for loop.

> + u32 ccbvid = rd_reg32(&ctrl->perfmon.ccb_id);
> + u16 ip_id = (secvid_ms & SECVID_MS_IPID_MASK) >> SECVID_MS_IPID_SHIFT;
> + u8 maj_rev = (secvid_ms & SECVID_MS_MAJ_REV_MASK) >>
> +   SECVID_MS_MAJ_REV_SHIFT;
> + u8 era = (ccbvid & CCBVID_ERA_MASK) >> CCBVID_ERA_SHIFT;
> +
> + if (era)/* This is '0' prior to CAAM ERA-6 */
> + return era;
> +
> + for (i = 0; i < ARRAY_SIZE(id); i++)
> + if (id[i].ip_id == ip_id && id[i].maj_rev == maj_rev)
> + return id[i].min_rev;
> +
> + return 0;
Should return -ENOTSUPP, to keep the semantics of caam_get_era().

> +}
> +
>  /**
>   * caam_get_era() - Return the ERA of the SEC on SoC, based
>   * on "sec-era" propery in the DTS. This property is updated by u-boot.
While here:
_optional_ ^^^ s/propery/property
Should also mention that ERA detection fallback relies on SEC registers (CCBVID
or SECVID).

>   **/
> -static int caam_get_era(void)
> +static int caam_get_era(struct caam_ctrl __iomem *ctrl)
>  {
>   struct device_node *caam_node;
>   int ret;
> @@ -410,7 +446,10 @@ static int caam_get_era(void)
>   ret = of_property_read_u32(caam_node, "fsl,sec-era", &prop);
>   of_node_put(caam_node);
>  
> - return ret ? -ENOTSUPP : prop;
> + if (!ret)
> + return prop;
> + else
> + return caam_get_era_from_hw(ctrl);
>  }
>  
>  static const struct of_device_id caam_match[] = {
> @@ -622,7 +661,7 @@ static int caam_probe(struct platform_device *pdev)
>   goto iounmap_ctrl;
>   }
>  
> - ctrlpriv->era = caam_get_era();
> + ctrlpriv->era = caam_get_era(ctrl);
>  
>   ret = of_platform_populate(nprop, caam_match, NULL, dev);
>   if (ret) {
> diff --git a/drivers/crypto/caam/regs.h b/drivers/crypto/caam/regs.h
> index fee3638..6f96d7b 100644
> --- a/drivers/crypto/caam/regs.h
> +++ b/drivers/crypto/caam/regs.h
> @@ -311,6 +311,12 @@ struct caam_perfmon {
>   u64 rsvd3;
>  
>   /* Component Instantiation Parameters   fe0-fff */
> +#define SECVID_MS_IPID_MASK  0x
> +#define SECVID_MS_IPID_SHIFT 16
> +#define SECVID_MS_MAJ_REV_MASK   0xff00
> +#define SECVID_MS_MAJ_REV_SHIFT  8
> +#define CCBVID_ERA_MASK  0xff00
> +#define CCBVID_ERA_SHIFT 24
Please add the defines in front of each register:
-SECVID_* before caam_id_ms
-CCBVID_* before ccb_id

>   u32 rtic_id;/* RVID - RTIC Version ID   */
>   u32 ccb_id; /* CCBVID - CCB Version ID  */
>   u32 cha_id_ms;  /* CHAV