Re: [PATCH qemu v2] ppc: Define SETFIELD for the ppc target

[Daniel Henrique Barboza <danielhb413@gmail.com>]

On 6/22/22 02:08, Alexey Kardashevskiy wrote:
> It keeps repeating, move it to the header. This uses __builtin_ffsl() to
> allow using the macros in #define.
> 
> This is not using the QEMU's FIELD macros as this would require changing
> all such macros found in skiboot (the PPC PowerNV firmware).
> 
> Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
> ---

Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>

> Changes:
> v2:
> * preserved the comment about skiboot
> * copied the actual macros from skiboot:
> https://github.com/open-power/skiboot/blob/master/include/bitutils.h#L31
> ---
>   include/hw/pci-host/pnv_phb3_regs.h | 16 ----------------
>   target/ppc/cpu.h                    | 12 ++++++++++++
>   hw/intc/pnv_xive.c                  | 20 --------------------
>   hw/intc/pnv_xive2.c                 | 20 --------------------
>   hw/pci-host/pnv_phb4.c              | 16 ----------------
>   5 files changed, 12 insertions(+), 72 deletions(-)
> 
> diff --git a/include/hw/pci-host/pnv_phb3_regs.h b/include/hw/pci-host/pnv_phb3_regs.h
> index a174ef1f7045..38f8ce9d7406 100644
> --- a/include/hw/pci-host/pnv_phb3_regs.h
> +++ b/include/hw/pci-host/pnv_phb3_regs.h
> @@ -12,22 +12,6 @@
>   
>   #include "qemu/host-utils.h"
>   
> -/*
> - * QEMU version of the GETFIELD/SETFIELD macros
> - *
> - * These are common with the PnvXive model.
> - */
> -static inline uint64_t GETFIELD(uint64_t mask, uint64_t word)
> -{
> -    return (word & mask) >> ctz64(mask);
> -}
> -
> -static inline uint64_t SETFIELD(uint64_t mask, uint64_t word,
> -                                uint64_t value)
> -{
> -    return (word & ~mask) | ((value << ctz64(mask)) & mask);
> -}
> -
>   /*
>    * PBCQ XSCOM registers
>    */
> diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h
> index 6d78078f379d..e45cc7a8c115 100644
> --- a/target/ppc/cpu.h
> +++ b/target/ppc/cpu.h
> @@ -47,6 +47,18 @@
>                                    PPC_BIT32(bs))
>   #define PPC_BITMASK8(bs, be)    ((PPC_BIT8(bs) - PPC_BIT8(be)) | PPC_BIT8(bs))
>   
> +/*
> + * QEMU version of the GETFIELD/SETFIELD macros
> + *
> + * It might be better to use the existing extract64() and
> + * deposit64() but this means that all the register definitions will
> + * change and become incompatible with the ones found in skiboot.
> + */
> +#define MASK_TO_LSH(m)          (__builtin_ffsl(m) - 1)
> +#define GETFIELD(m, v)          (((v) & (m)) >> MASK_TO_LSH(m))
> +#define SETFIELD(m, v, val) \
> +        (((v) & ~(m)) | ((((typeof(v))(val)) << MASK_TO_LSH(m)) & (m)))
> +
>   /*****************************************************************************/
>   /* Exception vectors definitions                                             */
>   enum {
> diff --git a/hw/intc/pnv_xive.c b/hw/intc/pnv_xive.c
> index 1ce1d7b07d63..c7b75ed12ee0 100644
> --- a/hw/intc/pnv_xive.c
> +++ b/hw/intc/pnv_xive.c
> @@ -66,26 +66,6 @@ static const XiveVstInfo vst_infos[] = {
>       qemu_log_mask(LOG_GUEST_ERROR, "XIVE[%x] - " fmt "\n",              \
>                     (xive)->chip->chip_id, ## __VA_ARGS__);
>   
> -/*
> - * QEMU version of the GETFIELD/SETFIELD macros
> - *
> - * TODO: It might be better to use the existing extract64() and
> - * deposit64() but this means that all the register definitions will
> - * change and become incompatible with the ones found in skiboot.
> - *
> - * Keep it as it is for now until we find a common ground.
> - */
> -static inline uint64_t GETFIELD(uint64_t mask, uint64_t word)
> -{
> -    return (word & mask) >> ctz64(mask);
> -}
> -
> -static inline uint64_t SETFIELD(uint64_t mask, uint64_t word,
> -                                uint64_t value)
> -{
> -    return (word & ~mask) | ((value << ctz64(mask)) & mask);
> -}
> -
>   /*
>    * When PC_TCTXT_CHIPID_OVERRIDE is configured, the PC_TCTXT_CHIPID
>    * field overrides the hardwired chip ID in the Powerbus operations
> diff --git a/hw/intc/pnv_xive2.c b/hw/intc/pnv_xive2.c
> index f31c53c28dd2..f22ce5ca59ae 100644
> --- a/hw/intc/pnv_xive2.c
> +++ b/hw/intc/pnv_xive2.c
> @@ -75,26 +75,6 @@ static const XiveVstInfo vst_infos[] = {
>       qemu_log_mask(LOG_GUEST_ERROR, "XIVE[%x] - " fmt "\n",              \
>                     (xive)->chip->chip_id, ## __VA_ARGS__);
>   
> -/*
> - * QEMU version of the GETFIELD/SETFIELD macros
> - *
> - * TODO: It might be better to use the existing extract64() and
> - * deposit64() but this means that all the register definitions will
> - * change and become incompatible with the ones found in skiboot.
> - *
> - * Keep it as it is for now until we find a common ground.
> - */
> -static inline uint64_t GETFIELD(uint64_t mask, uint64_t word)
> -{
> -    return (word & mask) >> ctz64(mask);
> -}
> -
> -static inline uint64_t SETFIELD(uint64_t mask, uint64_t word,
> -                                uint64_t value)
> -{
> -    return (word & ~mask) | ((value << ctz64(mask)) & mask);
> -}
> -
>   /*
>    * TODO: Document block id override
>    */
> diff --git a/hw/pci-host/pnv_phb4.c b/hw/pci-host/pnv_phb4.c
> index 6594016121a3..5d72c0c432b2 100644
> --- a/hw/pci-host/pnv_phb4.c
> +++ b/hw/pci-host/pnv_phb4.c
> @@ -31,22 +31,6 @@
>       qemu_log_mask(LOG_GUEST_ERROR, "phb4_pec[%d:%d]: " fmt "\n",        \
>                     (pec)->chip_id, (pec)->index, ## __VA_ARGS__)
>   
> -/*
> - * QEMU version of the GETFIELD/SETFIELD macros
> - *
> - * These are common with the PnvXive model.
> - */
> -static inline uint64_t GETFIELD(uint64_t mask, uint64_t word)
> -{
> -    return (word & mask) >> ctz64(mask);
> -}
> -
> -static inline uint64_t SETFIELD(uint64_t mask, uint64_t word,
> -                                uint64_t value)
> -{
> -    return (word & ~mask) | ((value << ctz64(mask)) & mask);
> -}
> -
>   static PCIDevice *pnv_phb4_find_cfg_dev(PnvPHB4 *phb)
>   {
>       PCIHostState *pci = PCI_HOST_BRIDGE(phb);