From netdev-owner@vger.kernel.org Mon Oct 23 10:15:13 2006 From: Stephen Hemminger Subject: [PATCH] sky2: 88E803X transmit lockup The reason sky2 driver was locking up on transmit on the Yukon-FE chipset is that it was misconfiguring the internal RAM buffer so the transmitter and receiver were sharing the same space. The code assumed there was 16K of RAM on Yukon-FE (taken from vendor driver sk98lin which is even more f*cked up on this). Then it assigned based on that. The giveaway was that the registers would only hold 9bits so both RX/TX had 0..1ff for space. It is a wonder it worked at all! This patch addresses this, and fixes an easily reproducible hang on Transmit. Only the Yukon-FE chip is Marvell 88E803X (10/100 only) are affected. Signed-off-by: Stephen Hemminger --- sky2.orig/drivers/net/sky2.c 2006-10-20 16:37:56.000000000 -0700 +++ sky2/drivers/net/sky2.c 2006-10-20 16:38:16.000000000 -0700 @@ -699,16 +699,10 @@ } -/* Assign Ram Buffer allocation. - * start and end are in units of 4k bytes - * ram registers are in units of 64bit words - */ -static void sky2_ramset(struct sky2_hw *hw, u16 q, u8 startk, u8 endk) +/* Assign Ram Buffer allocation in units of 64bit (8 bytes) */ +static void sky2_ramset(struct sky2_hw *hw, u16 q, u32 start, u32 end) { - u32 start, end; - - start = startk * 4096/8; - end = (endk * 4096/8) - 1; + pr_debug(PFX "q %d %#x %#x\n", q, start, end); sky2_write8(hw, RB_ADDR(q, RB_CTRL), RB_RST_CLR); sky2_write32(hw, RB_ADDR(q, RB_START), start); @@ -717,7 +711,7 @@ sky2_write32(hw, RB_ADDR(q, RB_RP), start); if (q == Q_R1 || q == Q_R2) { - u32 space = (endk - startk) * 4096/8; + u32 space = end - start + 1; u32 tp = space - space/4; /* On receive queue's set the thresholds @@ -1199,19 +1193,16 @@ sky2_mac_init(hw, port); - /* Determine available ram buffer space (in 4K blocks). - * Note: not sure about the FE setting below yet - */ - if (hw->chip_id == CHIP_ID_YUKON_FE) - ramsize = 4; - else - ramsize = sky2_read8(hw, B2_E_0); + /* Determine available ram buffer space in qwords. */ + ramsize = sky2_read8(hw, B2_E_0) * 4096/8; - /* Give transmitter one third (rounded up) */ - rxspace = ramsize - (ramsize + 2) / 3; + if (ramsize > 6*1024/8) + rxspace = ramsize - (ramsize + 2) / 3; + else + rxspace = ramsize / 2; - sky2_ramset(hw, rxqaddr[port], 0, rxspace); - sky2_ramset(hw, txqaddr[port], rxspace, ramsize); + sky2_ramset(hw, rxqaddr[port], 0, rxspace-1); + sky2_ramset(hw, txqaddr[port], rxspace, ramsize-1); /* Make sure SyncQ is disabled */ sky2_write8(hw, RB_ADDR(port == 0 ? Q_XS1 : Q_XS2, RB_CTRL),