lkml.org 
[lkml]   [2017]   [Aug]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [PATCH] tpm_tis: fix stall after iowrite*()s
Date
On Monday 14 August 2017 17:53:47, Haris Okanovic wrote:
> --- a/drivers/char/tpm/tpm_tis.c
> +++ b/drivers/char/tpm/tpm_tis.c
> @@ -52,6 +52,22 @@ static inline struct tpm_tis_tcg_phy
> *to_tpm_tis_tcg_phy(struct tpm_tis_data *da return container_of(data,
> struct tpm_tis_tcg_phy, priv);
> }
>
> +static inline void tpm_tis_iowrite8(u8 b, void __iomem *iobase, u32 addr)
> +{
> + iowrite8(b, iobase + addr);
> +#ifdef CONFIG_PREEMPT_RT_FULL
> + ioread8(iobase + TPM_ACCESS(0));
> +#endif
> +}

Maybe add some comment why an iorad8 is actually requried after each write on
RT. Currently it is rather obvious why this additional read is necessary. But
is this still the case in a year?

> +static inline void tpm_tis_iowrite32(u32 b, void __iomem *iobase, u32 addr)
> +{
> + iowrite32(b, iobase + addr);
> +#ifdef CONFIG_PREEMPT_RT_FULL
> + ioread8(iobase + TPM_ACCESS(0));
> +#endif
> +}

Same applies here. Or add a comment above both functions describing their
purpose.

Just my 2 cents

Best regards,
Alexander

\
 
 \ /
  Last update: 2017-08-15 08:11    [W:0.454 / U:0.696 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site