1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2000-2003 Silicon Graphics, Inc. All rights reserved.
7  */
8 
9 #include <linux/pci.h>
10 #include <linux/module.h>
11 #include <asm/io.h>
12 #include <asm/delay.h>
13 #include <asm/sn/simulator.h>
14 #include <asm/sn/pda.h>
15 #include <asm/sn/sn_cpuid.h>
16 
17 /**
18  * sn_io_addr - convert an in/out port to an i/o address
19  * @port: port to convert
20  *
21  * Legacy in/out instructions are converted to ld/st instructions
22  * on IA64.  This routine will convert a port number into a valid
23  * SN i/o address.  Used by sn_in*() and sn_out*().
24  */
25 void *
sn_io_addr(unsigned long port)26 sn_io_addr(unsigned long port)
27 {
28 	if (!IS_RUNNING_ON_SIMULATOR()) {
29 		/* On sn2, legacy I/O ports don't point at anything */
30 		if (port < 64*1024)
31 			return 0;
32 		return( (void *)  (port | __IA64_UNCACHED_OFFSET));
33 	} else {
34 		/* but the simulator uses them... */
35 		unsigned long addr;
36 
37 		/*
38  		 * word align port, but need more than 10 bits
39  		 * for accessing registers in bedrock local block
40  		 * (so we don't do port&0xfff)
41  		 */
42 		addr = 0xc0000087cc000000 | ((port >> 2) << 12);
43 		if ((port >= 0x1f0 && port <= 0x1f7) || port == 0x3f6 || port == 0x3f7)
44 			addr |= port;
45 		return(void *) addr;
46 	}
47 }
48 
49 EXPORT_SYMBOL(sn_io_addr);
50 
51 /**
52  * sn_mmiob - I/O space memory barrier
53  *
54  * Acts as a memory mapped I/O barrier for platforms that queue writes to
55  * I/O space.  This ensures that subsequent writes to I/O space arrive after
56  * all previous writes.  For most ia64 platforms, this is a simple
57  * 'mf.a' instruction.  For other platforms, mmiob() may have to read
58  * a chipset register to ensure ordering.
59  *
60  * On SN2, we wait for the PIO_WRITE_STATUS SHub register to clear.
61  * See PV 871084 for details about the WAR about zero value.
62  *
63  */
64 void
sn_mmiob(void)65 sn_mmiob (void)
66 {
67 	while ((((volatile unsigned long) (*pda.pio_write_status_addr)) & SH_PIO_WRITE_STATUS_0_PENDING_WRITE_COUNT_MASK) !=
68 				SH_PIO_WRITE_STATUS_0_PENDING_WRITE_COUNT_MASK)
69 		udelay(1);
70 }
71