Re: [PATCH net-next] net: stmmac: Add support for CBS QDISC

[Jose Abreu <Jose.Abreu@synopsys.com>]

++ SH Maintainers
++ SH ML

Hi SH Maintainers,

On 27-06-2018 15:15, kbuild test robot wrote:
> Hi Jose,
>
> I love your patch! Perhaps something to improve:
>
> [auto build test WARNING on net-next/master]
>
> url:    https://urldefense.proofpoint.com/v2/url?u=https-3A__github.com_0day-2Dci_linux_commits_Jose-2DAbreu_net-2Dstmmac-2DAdd-2Dsupport-2Dfor-2DCBS-2DQDISC_20180627-2D214704&d=DwIBAg&c=DPL6_X_6JkXFx7AXWqB0tg&r=WHDsc6kcWAl4i96Vm5hJ_19IJiuxx_p_Rzo2g-uHDKw&m=YIae3rrFzqYg_5b4eVIAXuyvT_EV0vKACS25rJugux8&s=qW5_vbinGt0OnyDfQ2wtKdb2ZGzCcLwq6Fmlaki61xw&e=
> config: sh-allyesconfig (attached as .config)
> compiler: sh4-linux-gnu-gcc (Debian 7.2.0-11) 7.2.0
> reproduce:
>         wget https://urldefense.proofpoint.com/v2/url?u=https-3A__raw.githubusercontent.com_intel_lkp-2Dtests_master_sbin_make.cross&d=DwIBAg&c=DPL6_X_6JkXFx7AXWqB0tg&r=WHDsc6kcWAl4i96Vm5hJ_19IJiuxx_p_Rzo2g-uHDKw&m=YIae3rrFzqYg_5b4eVIAXuyvT_EV0vKACS25rJugux8&s=4nNar4fgVZq0LjrPKIZP30nxVUY4yeu5QeyKbmlsu8A&e= -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # save the attached .config to linux build tree
>         GCC_VERSION=7.2.0 make.cross ARCH=sh 
>
> All warnings (new ones prefixed by >>):
>
>    In file included from ./arch/sh/include/generated/asm/div64.h:1:0,
>                     from include/linux/kernel.h:174,
>                     from include/linux/list.h:9,
>                     from include/linux/timer.h:5,
>                     from include/linux/workqueue.h:9,
>                     from include/net/pkt_cls.h:6,
>                     from drivers/net//ethernet/stmicro/stmmac/stmmac_tc.c:7:
>    drivers/net//ethernet/stmicro/stmmac/stmmac_tc.c: In function 'tc_setup_cbs':
>    include/asm-generic/div64.h:222:28: warning: comparison of distinct pointer types lacks a cast
>      (void)(((typeof((n)) *)0) == ((uint64_t *)0)); \
>                                ^
>>> drivers/net//ethernet/stmicro/stmmac/stmmac_tc.c:325:2: note: in expansion of macro 'do_div'
>      do_div(value, speed_div);
>      ^~~~~~
>    include/asm-generic/div64.h:222:28: warning: comparison of distinct pointer types lacks a cast
>      (void)(((typeof((n)) *)0) == ((uint64_t *)0)); \

I'm not seeing the reason for this warning as I'm using a 64 bit
var. I guess the warning is appearing only because its signed
[see source bellow]. Is this not supported?

Thanks and Best Regards,
Jose Miguel Abreu

>                                ^
>    drivers/net//ethernet/stmicro/stmmac/stmmac_tc.c:329:2: note: in expansion of macro 'do_div'
>      do_div(value, speed_div);
>      ^~~~~~
>
> vim +/do_div +325 drivers/net//ethernet/stmicro/stmmac/stmmac_tc.c
>
>    291	
>    292	static int tc_setup_cbs(struct stmmac_priv *priv,
>    293				struct tc_cbs_qopt_offload *qopt)
>    294	{
>    295		u32 tx_queues_count = priv->plat->tx_queues_to_use;
>    296		u32 queue = qopt->queue;
>    297		u32 ptr, speed_div;
>    298		u32 mode_to_use;
>    299		s64 value;
>    300		int ret;
>    301	
>    302		/* Queue 0 is not AVB capable */
>    303		if (queue <= 0 || queue >= tx_queues_count)
>    304			return -EINVAL;
>    305		if (priv->speed != SPEED_100 && priv->speed != SPEED_1000)
>    306			return -EOPNOTSUPP;
>    307	
>    308		mode_to_use = priv->plat->tx_queues_cfg[queue].mode_to_use;
>    309		if (mode_to_use == MTL_QUEUE_DCB && qopt->enable) {
>    310			ret = stmmac_dma_qmode(priv, priv->ioaddr, queue, MTL_QUEUE_AVB);
>    311			if (ret)
>    312				return ret;
>    313	
>    314			priv->plat->tx_queues_cfg[queue].mode_to_use = MTL_QUEUE_AVB;
>    315		} else if (!qopt->enable) {
>    316			return stmmac_dma_qmode(priv, priv->ioaddr, queue, MTL_QUEUE_DCB);
>    317		}
>    318	
>    319		/* Port Transmit Rate and Speed Divider */
>    320		ptr = (priv->speed == SPEED_100) ? 4 : 8;
>    321		speed_div = (priv->speed == SPEED_100) ? 100000 : 1000000;
>    322	
>    323		/* Final adjustments for HW */
>    324		value = qopt->idleslope * 1024 * ptr;
>  > 325		do_div(value, speed_div);
>    326		priv->plat->tx_queues_cfg[queue].idle_slope = value & GENMASK(31, 0);
>    327	
>    328		value = -qopt->sendslope * 1024UL * ptr;
>    329		do_div(value, speed_div);
>    330		priv->plat->tx_queues_cfg[queue].send_slope = value & GENMASK(31, 0);
>    331	
>    332		value = qopt->hicredit * 1024 * 8;
>    333		priv->plat->tx_queues_cfg[queue].high_credit = value & GENMASK(31, 0);
>    334	
>    335		value = qopt->locredit * 1024 * 8;
>    336		priv->plat->tx_queues_cfg[queue].low_credit = value & GENMASK(31, 0);
>    337	
>    338		ret = stmmac_config_cbs(priv, priv->hw,
>    339					priv->plat->tx_queues_cfg[queue].send_slope,
>    340					priv->plat->tx_queues_cfg[queue].idle_slope,
>    341					priv->plat->tx_queues_cfg[queue].high_credit,
>    342					priv->plat->tx_queues_cfg[queue].low_credit,
>    343					queue);
>    344		if (ret)
>    345			return ret;
>    346	
>    347		dev_info(priv->device, "CBS queue %d: send %d, idle %d, hi %d, lo %d\n",
>    348				queue, qopt->sendslope, qopt->idleslope,
>    349				qopt->hicredit, qopt->locredit);
>    350		return 0;
>    351	}
>    352	
>
> ---
> 0-DAY kernel test infrastructure                Open Source Technology Center
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