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Revision 8f4fd86aa5d6aa122619623910065d236592e37c authored by David Woodhouse on 06 January 2021, 15:39:55 UTC, committed by Juergen Gross on 13 January 2021, 15:12:03 UTC 
xen: Set platform PCI device INTX affinity to CPU0
 
With INTX or GSI delivery, Xen uses the event channel structures of CPU0.

If the interrupt gets handled by Linux on a different CPU, then no events
are seen as pending. Rather than introducing locking to allow other CPUs
to process CPU0's events, just ensure that the PCI interrupts happens
only on CPU0.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20210106153958.584169-3-dwmw2@infradead.org
Signed-off-by: Juergen Gross <jgross@suse.com>
1 parent 3499ba8
Raw File
bt455.h 
/*
 *	linux/drivers/video/bt455.h
 *
 *	Copyright 2003  Thiemo Seufer <seufer@csv.ica.uni-stuttgart.de>
 *	Copyright 2016  Maciej W. Rozycki <macro@linux-mips.org>
 *
 *	This file is subject to the terms and conditions of the GNU General
 *	Public License. See the file COPYING in the main directory of this
 *	archive for more details.
 */
#include <linux/types.h>

/*
 * Bt455 byte-wide registers, 32-bit aligned.
 */
struct bt455_regs {
	volatile u8 addr_cmap;
	u8 pad0[3];
	volatile u8 addr_cmap_data;
	u8 pad1[3];
	volatile u8 addr_clr;
	u8 pad2[3];
	volatile u8 addr_ovly;
	u8 pad3[3];
};

static inline void bt455_select_reg(struct bt455_regs *regs, int ir)
{
	mb();
	regs->addr_cmap = ir & 0x0f;
}

static inline void bt455_reset_reg(struct bt455_regs *regs)
{
	mb();
	regs->addr_clr = 0;
}

/*
 * Read/write to a Bt455 color map register.
 */
static inline void bt455_read_cmap_next(struct bt455_regs *regs, u8 *grey)
{
	mb();
	regs->addr_cmap_data;
	rmb();
	*grey = regs->addr_cmap_data & 0xf;
	rmb();
	regs->addr_cmap_data;
}

static inline void bt455_write_cmap_next(struct bt455_regs *regs, u8 grey)
{
	wmb();
	regs->addr_cmap_data = 0x0;
	wmb();
	regs->addr_cmap_data = grey & 0xf;
	wmb();
	regs->addr_cmap_data = 0x0;
}

static inline void bt455_write_ovly_next(struct bt455_regs *regs, u8 grey)
{
	wmb();
	regs->addr_ovly = 0x0;
	wmb();
	regs->addr_ovly = grey & 0xf;
	wmb();
	regs->addr_ovly = 0x0;
}

static inline void bt455_read_cmap_entry(struct bt455_regs *regs,
					 int cr, u8 *grey)
{
	bt455_select_reg(regs, cr);
	bt455_read_cmap_next(regs, grey);
}

static inline void bt455_write_cmap_entry(struct bt455_regs *regs,
					  int cr, u8 grey)
{
	bt455_select_reg(regs, cr);
	bt455_write_cmap_next(regs, grey);
}

static inline void bt455_write_ovly_entry(struct bt455_regs *regs, u8 grey)
{
	bt455_reset_reg(regs);
	bt455_write_ovly_next(regs, grey);
}
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