1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *      linux/arch/alpha/kernel/core_polaris.c
4  *
5  * POLARIS chip-specific code
6  */
7 
8 #define __EXTERN_INLINE inline
9 #include <asm/io.h>
10 #include <asm/core_polaris.h>
11 #undef __EXTERN_INLINE
12 
13 #include <linux/types.h>
14 #include <linux/pci.h>
15 #include <linux/sched.h>
16 #include <linux/init.h>
17 
18 #include <asm/ptrace.h>
19 
20 #include "proto.h"
21 #include "pci_impl.h"
22 
23 /*
24  * BIOS32-style PCI interface:
25  */
26 
27 #define DEBUG_CONFIG 0
28 
29 #if DEBUG_CONFIG
30 # define DBG_CFG(args)	printk args
31 #else
32 # define DBG_CFG(args)
33 #endif
34 
35 
36 /*
37  * Given a bus, device, and function number, compute resulting
38  * configuration space address.  This is fairly straightforward
39  * on POLARIS, since the chip itself generates Type 0 or Type 1
40  * cycles automatically depending on the bus number (Bus 0 is
41  * hardwired to Type 0, all others are Type 1.  Peer bridges
42  * are not supported).
43  *
44  * All types:
45  *
46  *  3 3 3 3|3 3 3 3|3 3 2 2|2 2 2 2|2 2 2 2|1 1 1 1|1 1 1 1|1 1
47  *  9 8 7 6|5 4 3 2|1 0 9 8|7 6 5 4|3 2 1 0|9 8 7 6|5 4 3 2|1 0 9 8|7 6 5 4|3 2 1 0
48  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
49  * |1|1|1|1|1|0|0|1|1|1|1|1|1|1|1|0|B|B|B|B|B|B|B|B|D|D|D|D|D|F|F|F|R|R|R|R|R|R|x|x|
50  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
51  *
52  *	23:16	bus number (8 bits = 128 possible buses)
53  *	15:11	Device number (5 bits)
54  *	10:8	function number
55  *	 7:2	register number
56  *
57  * Notes:
58  *	The function number selects which function of a multi-function device
59  *	(e.g., scsi and ethernet).
60  *
61  *	The register selects a DWORD (32 bit) register offset.  Hence it
62  *	doesn't get shifted by 2 bits as we want to "drop" the bottom two
63  *	bits.
64  */
65 
66 static int
mk_conf_addr(struct pci_bus * pbus,unsigned int device_fn,int where,unsigned long * pci_addr,u8 * type1)67 mk_conf_addr(struct pci_bus *pbus, unsigned int device_fn, int where,
68 	     unsigned long *pci_addr, u8 *type1)
69 {
70 	u8 bus = pbus->number;
71 
72 	*type1 = (bus == 0) ? 0 : 1;
73 	*pci_addr = (bus << 16) | (device_fn << 8) | (where) |
74 		    POLARIS_DENSE_CONFIG_BASE;
75 
76         DBG_CFG(("mk_conf_addr(bus=%d ,device_fn=0x%x, where=0x%x,"
77                  " returning address 0x%p\n"
78                  bus, device_fn, where, *pci_addr));
79 
80 	return 0;
81 }
82 
83 static int
polaris_read_config(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 * value)84 polaris_read_config(struct pci_bus *bus, unsigned int devfn, int where,
85 		    int size, u32 *value)
86 {
87 	unsigned long addr;
88 	unsigned char type1;
89 
90 	if (mk_conf_addr(bus, devfn, where, &addr, &type1))
91                 return PCIBIOS_DEVICE_NOT_FOUND;
92 
93 	switch (size) {
94 	case 1:
95 		*value = __kernel_ldbu(*(vucp)addr);
96 		break;
97 	case 2:
98 		*value = __kernel_ldwu(*(vusp)addr);
99 		break;
100 	case 4:
101 		*value = *(vuip)addr;
102 		break;
103 	}
104 
105 	return PCIBIOS_SUCCESSFUL;
106 }
107 
108 
109 static int
polaris_write_config(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 value)110 polaris_write_config(struct pci_bus *bus, unsigned int devfn, int where,
111 		     int size, u32 value)
112 {
113 	unsigned long addr;
114 	unsigned char type1;
115 
116 	if (mk_conf_addr(bus, devfn, where, &addr, &type1))
117                 return PCIBIOS_DEVICE_NOT_FOUND;
118 
119 	switch (size) {
120 	case 1:
121 		__kernel_stb(value, *(vucp)addr);
122 		mb();
123 		__kernel_ldbu(*(vucp)addr);
124 		break;
125 	case 2:
126 		__kernel_stw(value, *(vusp)addr);
127 		mb();
128 		__kernel_ldwu(*(vusp)addr);
129 		break;
130 	case 4:
131 		*(vuip)addr = value;
132 		mb();
133 		*(vuip)addr;
134 		break;
135 	}
136 
137 	return PCIBIOS_SUCCESSFUL;
138 }
139 
140 struct pci_ops polaris_pci_ops =
141 {
142 	.read =		polaris_read_config,
143 	.write =	polaris_write_config,
144 };
145 
146 void __init
polaris_init_arch(void)147 polaris_init_arch(void)
148 {
149 	struct pci_controller *hose;
150 
151 	/* May need to initialize error reporting (see PCICTL0/1), but
152 	 * for now assume that the firmware has done the right thing
153 	 * already.
154 	 */
155 #if 0
156 	printk("polaris_init_arch(): trusting firmware for setup\n");
157 #endif
158 
159 	/*
160 	 * Create our single hose.
161 	 */
162 
163 	pci_isa_hose = hose = alloc_pci_controller();
164 	hose->io_space = &ioport_resource;
165 	hose->mem_space = &iomem_resource;
166 	hose->index = 0;
167 
168 	hose->sparse_mem_base = 0;
169 	hose->dense_mem_base = POLARIS_DENSE_MEM_BASE - IDENT_ADDR;
170 	hose->sparse_io_base = 0;
171 	hose->dense_io_base = POLARIS_DENSE_IO_BASE - IDENT_ADDR;
172 
173 	hose->sg_isa = hose->sg_pci = NULL;
174 
175 	/* The I/O window is fixed at 2G @ 2G.  */
176 	__direct_map_base = 0x80000000;
177 	__direct_map_size = 0x80000000;
178 }
179 
180 static inline void
polaris_pci_clr_err(void)181 polaris_pci_clr_err(void)
182 {
183 	*(vusp)POLARIS_W_STATUS;
184 	/* Write 1's to settable bits to clear errors */
185 	*(vusp)POLARIS_W_STATUS = 0x7800;
186 	mb();
187 	*(vusp)POLARIS_W_STATUS;
188 }
189 
190 void
polaris_machine_check(unsigned long vector,unsigned long la_ptr)191 polaris_machine_check(unsigned long vector, unsigned long la_ptr)
192 {
193 	/* Clear the error before any reporting.  */
194 	mb();
195 	mb();
196 	draina();
197 	polaris_pci_clr_err();
198 	wrmces(0x7);
199 	mb();
200 
201 	process_mcheck_info(vector, la_ptr, "POLARIS",
202 			    mcheck_expected(0));
203 }
204