Commit 470ea7eb authored by Stephen Hemminger's avatar Stephen Hemminger Committed by Jeff Garzik
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[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: default avatarStephen Hemminger <shemminger@osdl.org>
Signed-off-by: default avatarJeff Garzik <jeff@garzik.org>
parent 7347b03d

drivers/net/sky2.c

+12 −21
Original line number Diff line number Diff line
@@ -699,16 +699,10 @@ static void sky2_mac_init(struct sky2_hw *hw, unsigned port) 


}



/* 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 @@ static void sky2_ramset(struct sky2_hw *hw, u16 q, u8 startk, u8 endk) 
	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 @@ static int sky2_up(struct net_device *dev) 


	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) */

	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),

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