Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Thu, 28 Apr 2022 23:35:36 +0200
From:   Francois Romieu <romieu@fr.zoreil.com>
To:     Wells Lu =?utf-8?B?5ZGC6Iqz6aiw?= <wells.lu@sunplus.com>
Cc:     Wells Lu <wellslutw@gmail.com>,
        "davem@davemloft.net" <davem@davemloft.net>,
        "kuba@kernel.org" <kuba@kernel.org>,
        "robh+dt@kernel.org" <robh+dt@kernel.org>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "p.zabel@pengutronix.de" <p.zabel@pengutronix.de>,
        "pabeni@redhat.com" <pabeni@redhat.com>,
        "krzk+dt@kernel.org" <krzk+dt@kernel.org>,
        "roopa@nvidia.com" <roopa@nvidia.com>,
        "andrew@lunn.ch" <andrew@lunn.ch>,
        "edumazet@google.com" <edumazet@google.com>
Subject: Re: [PATCH net-next v9 2/2] net: ethernet: Add driver for Sunplus
 SP7021
Message-ID: <YmsIqDPjvZKbbKov@electric-eye.fr.zoreil.com>
References: <1650882640-7106-1-git-send-email-wellslutw@gmail.com>
 <1650882640-7106-3-git-send-email-wellslutw@gmail.com>
 <Ymh3si+MTg5i0Bnl@electric-eye.fr.zoreil.com>
 <ff2077684c4c45fca929a8f61447242b@sphcmbx02.sunplus.com.tw>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <ff2077684c4c45fca929a8f61447242b@sphcmbx02.sunplus.com.tw>
Precedence: bulk

Wells Lu eh
3i(0 <wells.lu@sunplus.com> :
[...]
> I will add disable_irq() and enable_irq() for spl2sw_rx_poll() and spl2sw_tx_poll() as shown below:
> 
> spl2sw_rx_poll():
> 
> 	wmb();	/* make sure settings are effective. */
> 	disable_irq(comm->irq);
> 	mask = readl(comm->l2sw_reg_base + L2SW_SW_INT_MASK_0);
> 	mask &= ~MAC_INT_RX;
> 	writel(mask, comm->l2sw_reg_base + L2SW_SW_INT_MASK_0);
> 	enable_irq(comm->irq);
> 
> spl2sw_tx_poll():
> 
> 	wmb();			/* make sure settings are effective. */
> 	disable_irq(comm->irq);
> 	mask = readl(comm->l2sw_reg_base + L2SW_SW_INT_MASK_0);
> 	mask &= ~MAC_INT_TX;
> 	writel(mask, comm->l2sw_reg_base + L2SW_SW_INT_MASK_0);
> 	enable_irq(comm->irq);
> 
> 
> Is the modification ok?

disable_irq prevents future irq processing but it does not help against irq
code currently running on a different cpu.

You may use plain spin_{lock / unlock} in IRQ context and
spin_{loq_irqsave / irq_restore} in NAPI context.

-- 
Ueimor