> -----Original Message----- > From: Ben Hutchings [mailto:bhutchings@xxxxxxxxxxxxxx] > Sent: Friday, May 27, 2011 1:56 AM > To: GuanXuetao > Cc: arnd@xxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; linux-arch@xxxxxxxxxxxxxxx; greg@xxxxxxxxx; netdev@xxxxxxxxxxxxxxx > Subject: Re: [PATCH 2/6] unicore32: add pkunity-v3 mac/net driver (umal) > > On Thu, 2011-05-26 at 11:36 +0000, GuanXuetao wrote: > [...] > > --- /dev/null > > +++ b/drivers/net/mac-puv3.c > [...] > > +/********************************************************************** > > + * Simple types > > + ********************************************************************* */ > > +enum umal_speed { > > + umal_speed_none = 0, > > + umal_speed_10 = SPEED_10, > > + umal_speed_100 = SPEED_100, > > + umal_speed_1000 = SPEED_1000, > > +}; > > Just use the numbers directly: 0, 10, 100, 1000. Applied. > > [...] > > +#define ETHER_ADDR_LEN 6 > > This is already called ETH_ALEN. Applied. > > [...] > > +/********************************************************************** > > + * DMA Descriptor structure > > + ********************************************************************* */ > > +struct umaldmadscr { > > + dma_addr_t PacketStartAddr; > > + int PacketSize; > > + dma_addr_t NextDescriptor; > > + struct umaldmadscr *NextDescriptor_Virt; > > +}; > > Linux naming convention for structure fields is words_with_underscores > not TitleCase. Ok, thanks. > > [...] > > +/********************************************************************** > > + * UMAL_MII_RESET(bus) > > + * > > + * Reset MII bus. > > + * > > + * Input parameters: > > + * bus - MDIO bus handle > > + * > > + * Return value: > > + * 0 if ok > > + ********************************************************************* */ > > Function documentation comments must follow the kernel-doc format. Ok, thanks. > > [...] > > +static int umaldma_add_rcvbuffer(struct umal_softc *sc, struct umaldma *d, > > + struct sk_buff *sb) > > +{ > [...] > > + /* > > + * Allocate a sk_buff if we don't already have one. > > + * If we do have an sk_buff, reset it so that it's empty. > > + * > > + * Note: sk_buffs don't seem to be guaranteed to have any sort > > + * of alignment when they are allocated. Therefore, allocate enough > > + * extra space to make sure that: > > + * > > + * 1. the data does not start in the middle of a cache line. > > + * 2. The data does not end in the middle of a cache line > > + * 3. The buffer can be aligned such that the IP addresses are > > + * naturally aligned. > > + * > > + * Remember, the SOCs MAC writes whole cache lines at a time, > > + * without reading the old contents first. So, if the sk_buff's > > + * data portion starts in the middle of a cache line, the SOC > > + * DMA will trash the beginning (and ending) portions. > > + */ > > + if (sb == NULL) { > > + sb_new = netdev_alloc_skb(dev, ENET_PACKET_SIZE + > > + SMP_CACHE_BYTES * 2 + NET_IP_ALIGN); > > + if (sb_new == NULL) { > > + pr_info("%s: sk_buff allocation failed\n", > > + d->umaldma_eth->umal_dev->name); > > + return -ENOBUFS; > > Surely -ENOMEM. Applied. > > > + } > > + skb_reserve(sb_new, 2); > > This presumably needs to be: > > skb_reserve(sb_new, SMP_CACHE_BYTES + NET_IP_ALIGN); > > unless you assume that the skb allocator will always ensure cache line > alignment (in which case, why use padding of SMP_CACHE_BYTES * 2?). Applied, thanks. Each packet address needs to be added by NET_IP_ALIGN. And I think that SMP_CACHE_BYTES is also necessary to guarantee correctness when invalidate dma cache lines. > > [...] > > +static void umaldma_tx_process(struct umal_softc *sc, struct umaldma *d, > > + int poll) > > +{ > > + struct net_device *dev = sc->umal_dev; > > + int curidx; > > + int hwidx; > > + struct umaldmadscr *dsc; > > + struct sk_buff *sb; > > + unsigned long flags; > > + int packets_handled = 0; > > + unsigned int int_status; > > + > > + spin_lock_irqsave(&(sc->umal_lock), flags); > > + > > + if (!netif_device_present(dev)) > > + return; > [...] > > This returns with the lock held! Applied, thanks. > > (This is not by any means a thorough review.) > > Ben. > > -- > Ben Hutchings, Senior Software Engineer, Solarflare > Not speaking for my employer; that's the marketing department's job. > They asked us to note that Solarflare product names are trademarked. Thanks Ben. I will submit next version after correcting the coding-style. Guan Xuetao -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
