Commit 78958433 authored by Jon Mason's avatar Jon Mason
Browse files

NTB: Enable Snoop on Primary Side 



Enable Snoop from Primary to Secondary side on BAR23 and BAR45 on all
TLPs.  Previously, Snoop was only enabled from Secondary to Primary
side.  This can have a performance improvement on some workloads.

Also, make the code more obvious about how the link is being enabled.

Signed-off-by: default avatarJon Mason <jon.mason@intel.com>
parent 58b88920

drivers/ntb/ntb_hw.c

+12 −5
Original line number Diff line number Diff line
@@ -1316,10 +1316,16 @@ static void ntb_hw_link_up(struct ntb_device *ndev) 
{

	if (ndev->conn_type == NTB_CONN_TRANSPARENT)

		ntb_link_event(ndev, NTB_LINK_UP);

	else

	else {

		u32 ntb_cntl;



		/* Let's bring the NTB link up */

		writel(NTB_CNTL_BAR23_SNOOP | NTB_CNTL_BAR45_SNOOP,

		       ndev->reg_ofs.lnk_cntl);

		ntb_cntl = readl(ndev->reg_ofs.lnk_cntl);

		ntb_cntl &= ~(NTB_CNTL_LINK_DISABLE | NTB_CNTL_CFG_LOCK);

		ntb_cntl |= NTB_CNTL_P2S_BAR23_SNOOP | NTB_CNTL_S2P_BAR23_SNOOP;

		ntb_cntl |= NTB_CNTL_P2S_BAR45_SNOOP | NTB_CNTL_S2P_BAR45_SNOOP;

		writel(ntb_cntl, ndev->reg_ofs.lnk_cntl);

	}

}



static void ntb_hw_link_down(struct ntb_device *ndev)
@@ -1333,8 +1339,9 @@ static void ntb_hw_link_down(struct ntb_device *ndev) 


	/* Bring NTB link down */

	ntb_cntl = readl(ndev->reg_ofs.lnk_cntl);

	ntb_cntl &= ~(NTB_CNTL_BAR23_SNOOP | NTB_CNTL_BAR45_SNOOP);

	ntb_cntl |= NTB_CNTL_LINK_DISABLE;

	ntb_cntl &= ~(NTB_CNTL_P2S_BAR23_SNOOP | NTB_CNTL_S2P_BAR23_SNOOP);

	ntb_cntl &= ~(NTB_CNTL_P2S_BAR45_SNOOP | NTB_CNTL_S2P_BAR45_SNOOP);

	ntb_cntl |= NTB_CNTL_LINK_DISABLE | NTB_CNTL_CFG_LOCK;

	writel(ntb_cntl, ndev->reg_ofs.lnk_cntl);

}

drivers/ntb/ntb_regs.h

+7 −5
Original line number Diff line number Diff line
@@ -145,8 +145,10 @@ 


#define NTB_CNTL_CFG_LOCK		(1 << 0)

#define NTB_CNTL_LINK_DISABLE		(1 << 1)

#define NTB_CNTL_BAR23_SNOOP	(1 << 2)

#define NTB_CNTL_BAR45_SNOOP	(1 << 6)

#define NTB_CNTL_S2P_BAR23_SNOOP	(1 << 2)

#define NTB_CNTL_P2S_BAR23_SNOOP	(1 << 4)

#define NTB_CNTL_S2P_BAR45_SNOOP	(1 << 6)

#define NTB_CNTL_P2S_BAR45_SNOOP	(1 << 8)

#define BWD_CNTL_LINK_DOWN		(1 << 16)



#define NTB_PPD_OFFSET		0x00D4