[U-Boot] [PATCH v4 16/25] riscv: Update supports_extension() to use desc from cpu driver

[Auer, Lukas]

Hi Bin,

On Wed, 2018-12-12 at 22:11 +0800, Bin Meng wrote:
> Hi Lukas,
> 
> On Wed, Dec 12, 2018 at 7:53 PM Auer, Lukas
> <lukas.auer at aisec.fraunhofer.de> wrote:
> > 
> > Hi Bin,
> > 
> > On Tue, 2018-12-11 at 23:11 -0800, Bin Meng wrote:
> > > This updates supports_extension() implementation to use the desc
> > > string from the cpu driver whenever possible, which avoids the
> > > reading of misa CSR for S-mode U-Boot.
> > > 
> > > Signed-off-by: Bin Meng <bmeng.cn at gmail.com>
> > > 
> > > ---
> > > 
> > > Changes in v4:
> > > - print warnings for S-mode without CONFIG_CPU
> > > 
> > > Changes in v3:
> > > - new patch to update supports_extension() to use desc from cpu
> > > driver
> > > 
> > > Changes in v2: None
> > > 
> > >  arch/riscv/cpu/cpu.c | 22 ++++++++++++++++++++++
> > >  1 file changed, 22 insertions(+)
> > > 
> > > diff --git a/arch/riscv/cpu/cpu.c b/arch/riscv/cpu/cpu.c
> > > index d3c59da..a2ebaf3 100644
> > > --- a/arch/riscv/cpu/cpu.c
> > > +++ b/arch/riscv/cpu/cpu.c
> > > @@ -5,8 +5,10 @@
> > > 
> > >  #include <common.h>
> > >  #include <cpu.h>
> > > +#include <dm.h>
> > >  #include <log.h>
> > >  #include <asm/csr.h>
> > > +#include <dm/uclass-internal.h>
> > > 
> > >  /*
> > >   * prior_stage_fdt_address must be stored in the data section
> > > since
> > > it is used
> > > @@ -16,7 +18,27 @@ phys_addr_t prior_stage_fdt_address
> > > __attribute__((section(".data")));
> > > 
> > >  static inline bool supports_extension(char ext)
> > >  {
> > > +#ifdef CONFIG_CPU
> > > +     struct udevice *dev;
> > > +     char desc[32];
> > > +
> > > +     uclass_find_first_device(UCLASS_CPU, &dev);
> > 
> > Sorry, I missed this before. Can you add error handling here to
> > catch
> > uclass_find_first_device returning an error or not finding a
> > device? It
> > would probably also make sense to print a warning message to the
> > user
> > in this case.
> > 
> 
> Added the error check in v5. Note only checking not finding a device
> (dev == NULL) is enough as if uclass_find_first_device() returns an
> error code, dev is NULL too.
> 

Thanks! The series looks good now!

Lukas

> > Other than that, this patch and the series look good!
> > Reviewed-by: Lukas Auer <lukas.auer at aisec.fraunhofer.de>
> > 
> 
> Regards,
> Bin