Re: [PATCH v3 net-next 4/5] net: ipa: introduce ipa_table_hash_support()

[Alexander Duyck]

On Fri, Feb 12, 2021 at 6:40 AM Alex Elder <elder@xxxxxxxxxx> wrote:
>
> Introduce a new function to abstract the knowledge of whether hashed
> routing and filter tables are supported for a given IPA instance.
>
> IPA v4.2 is the only one that doesn't support hashed tables (now
> and for the foreseeable future), but the name of the helper function
> is better for explaining what's going on.
>
> Signed-off-by: Alex Elder <elder@xxxxxxxxxx>
> ---
> v2: - Update copyrights.
>
>  drivers/net/ipa/ipa_cmd.c   |  2 +-
>  drivers/net/ipa/ipa_table.c | 16 +++++++++-------
>  drivers/net/ipa/ipa_table.h |  8 +++++++-
>  3 files changed, 17 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/net/ipa/ipa_cmd.c b/drivers/net/ipa/ipa_cmd.c
> index fd8bf6468d313..35e35852c25c5 100644
> --- a/drivers/net/ipa/ipa_cmd.c
> +++ b/drivers/net/ipa/ipa_cmd.c
> @@ -268,7 +268,7 @@ static bool ipa_cmd_register_write_valid(struct ipa *ipa)
>         /* If hashed tables are supported, ensure the hash flush register
>          * offset will fit in a register write IPA immediate command.
>          */
> -       if (ipa->version != IPA_VERSION_4_2) {
> +       if (ipa_table_hash_support(ipa)) {
>                 offset = ipa_reg_filt_rout_hash_flush_offset(ipa->version);
>                 name = "filter/route hash flush";
>                 if (!ipa_cmd_register_write_offset_valid(ipa, name, offset))
> diff --git a/drivers/net/ipa/ipa_table.c b/drivers/net/ipa/ipa_table.c
> index 32e2d3e052d55..baaab3dd0e63c 100644
> --- a/drivers/net/ipa/ipa_table.c
> +++ b/drivers/net/ipa/ipa_table.c
> @@ -1,7 +1,7 @@
>  // SPDX-License-Identifier: GPL-2.0
>
>  /* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
> - * Copyright (C) 2018-2020 Linaro Ltd.
> + * Copyright (C) 2018-2021 Linaro Ltd.
>   */
>
>  #include <linux/types.h>
> @@ -239,6 +239,11 @@ static void ipa_table_validate_build(void)
>
>  #endif /* !IPA_VALIDATE */
>
> +bool ipa_table_hash_support(struct ipa *ipa)
> +{
> +       return ipa->version != IPA_VERSION_4_2;
> +}
> +

Since this is only a single comparison it might make more sense to
make this a static inline and place it in ipa.h. Otherwise you are
just bloating the code up to jump to such a small function.

>  /* Zero entry count means no table, so just return a 0 address */
>  static dma_addr_t ipa_table_addr(struct ipa *ipa, bool filter_mask, u16 count)
>  {
> @@ -412,8 +417,7 @@ int ipa_table_hash_flush(struct ipa *ipa)
>         struct gsi_trans *trans;
>         u32 val;
>
> -       /* IPA version 4.2 does not support hashed tables */
> -       if (ipa->version == IPA_VERSION_4_2)
> +       if (!ipa_table_hash_support(ipa))
>                 return 0;
>
>         trans = ipa_cmd_trans_alloc(ipa, 1);
> @@ -531,8 +535,7 @@ static void ipa_filter_config(struct ipa *ipa, bool modem)
>         enum gsi_ee_id ee_id = modem ? GSI_EE_MODEM : GSI_EE_AP;
>         u32 ep_mask = ipa->filter_map;
>
> -       /* IPA version 4.2 has no hashed route tables */
> -       if (ipa->version == IPA_VERSION_4_2)
> +       if (!ipa_table_hash_support(ipa))
>                 return;
>
>         while (ep_mask) {
> @@ -582,8 +585,7 @@ static void ipa_route_config(struct ipa *ipa, bool modem)
>  {
>         u32 route_id;
>
> -       /* IPA version 4.2 has no hashed route tables */
> -       if (ipa->version == IPA_VERSION_4_2)
> +       if (!ipa_table_hash_support(ipa))
>                 return;
>
>         for (route_id = 0; route_id < IPA_ROUTE_COUNT_MAX; route_id++)
> diff --git a/drivers/net/ipa/ipa_table.h b/drivers/net/ipa/ipa_table.h
> index 78038d14fcea9..1a68d20f19d6a 100644
> --- a/drivers/net/ipa/ipa_table.h
> +++ b/drivers/net/ipa/ipa_table.h
> @@ -1,7 +1,7 @@
>  /* SPDX-License-Identifier: GPL-2.0 */
>
>  /* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
> - * Copyright (C) 2019-2020 Linaro Ltd.
> + * Copyright (C) 2019-2021 Linaro Ltd.
>   */
>  #ifndef _IPA_TABLE_H_
>  #define _IPA_TABLE_H_
> @@ -51,6 +51,12 @@ static inline bool ipa_filter_map_valid(struct ipa *ipa, u32 filter_mask)
>
>  #endif /* !IPA_VALIDATE */
>
> +/**
> + * ipa_table_hash_support() - Return true if hashed tables are supported
> + * @ipa:       IPA pointer
> + */
> +bool ipa_table_hash_support(struct ipa *ipa);
> +
>  /**
>   * ipa_table_reset() - Reset filter and route tables entries to "none"
>   * @ipa:       IPA pointer

Just define the function here and make it a static inline.