2 * ip22-mc.c: Routines for manipulating SGI Memory Controller.
4 * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
5 * Copyright (C) 1999 Andrew R. Baker (andrewb@uab.edu) - Indigo2 changes
6 * Copyright (C) 2003 Ladislav Michl (ladis@linux-mips.org)
9 #include <linux/init.h>
10 #include <linux/module.h>
11 #include <linux/kernel.h>
14 #include <asm/bootinfo.h>
15 #include <asm/sgialib.h>
16 #include <asm/sgi/mc.h>
17 #include <asm/sgi/hpc3.h>
18 #include <asm/sgi/ip22.h>
20 struct sgimc_regs *sgimc;
24 static inline unsigned long get_bank_addr(unsigned int memconfig)
26 return ((memconfig & SGIMC_MCONFIG_BASEADDR) <<
27 ((sgimc->systemid & SGIMC_SYSID_MASKREV) >= 5 ? 24 : 22));
30 static inline unsigned long get_bank_size(unsigned int memconfig)
32 return ((memconfig & SGIMC_MCONFIG_RMASK) + 0x0100) <<
33 ((sgimc->systemid & SGIMC_SYSID_MASKREV) >= 5 ? 16 : 14);
36 static inline unsigned int get_bank_config(int bank)
38 unsigned int res = bank > 1 ? sgimc->mconfig1 : sgimc->mconfig0;
39 return bank % 2 ? res & 0xffff : res >> 16;
48 * Detect installed memory, do some sanity checks and notify kernel about it
50 static void probe_memory(void)
52 int i, j, found, cnt = 0;
54 struct mem space[2] = {{SGIMC_SEG0_BADDR, 0}, {SGIMC_SEG1_BADDR, 0}};
56 printk(KERN_INFO "MC: Probing memory configuration:\n");
57 for (i = 0; i < ARRAY_SIZE(bank); i++) {
58 unsigned int tmp = get_bank_config(i);
59 if (!(tmp & SGIMC_MCONFIG_BVALID))
62 bank[cnt].size = get_bank_size(tmp);
63 bank[cnt].addr = get_bank_addr(tmp);
64 printk(KERN_INFO " bank%d: %3ldM @ %08lx\n",
65 i, bank[cnt].size / 1024 / 1024, bank[cnt].addr);
69 /* And you thought bubble sort is dead algorithm... */
71 unsigned long addr, size;
74 for (i = 1; i < cnt; i++)
75 if (bank[i-1].addr > bank[i].addr) {
78 bank[i].addr = bank[i-1].addr;
79 bank[i].size = bank[i-1].size;
80 bank[i-1].addr = addr;
81 bank[i-1].size = size;
86 /* Figure out how are memory banks mapped into spaces */
87 for (i = 0; i < cnt; i++) {
89 for (j = 0; j < ARRAY_SIZE(space) && !found; j++)
90 if (space[j].addr + space[j].size == bank[i].addr) {
91 space[j].size += bank[i].size;
94 /* There is either hole or overlapping memory */
96 printk(KERN_CRIT "MC: Memory configuration mismatch "
97 "(%08lx), expect Bus Error soon\n",
101 for (i = 0; i < ARRAY_SIZE(space); i++)
103 add_memory_region(space[i].addr, space[i].size,
107 void __init sgimc_init(void)
111 /* ioremap can't fail */
112 sgimc = (struct sgimc_regs *)
113 ioremap(SGIMC_BASE, sizeof(struct sgimc_regs));
115 printk(KERN_INFO "MC: SGI memory controller Revision %d\n",
116 (int) sgimc->systemid & SGIMC_SYSID_MASKREV);
118 /* Place the MC into a known state. This must be done before
119 * interrupts are first enabled etc.
122 /* Step 0: Make sure we turn off the watchdog in case it's
123 * still running (which might be the case after a
126 tmp = sgimc->cpuctrl0;
127 tmp &= ~SGIMC_CCTRL0_WDOG;
128 sgimc->cpuctrl0 = tmp;
130 /* Step 1: The CPU/GIO error status registers will not latch
131 * up a new error status until the register has been
132 * cleared by the cpu. These status registers are
133 * cleared by writing any value to them.
135 sgimc->cstat = sgimc->gstat = 0;
137 /* Step 2: Enable all parity checking in cpu control register
140 tmp = sgimc->cpuctrl0;
141 tmp |= (SGIMC_CCTRL0_EPERRGIO | SGIMC_CCTRL0_EPERRMEM |
142 SGIMC_CCTRL0_R4KNOCHKPARR);
143 sgimc->cpuctrl0 = tmp;
145 /* Step 3: Setup the MC write buffer depth, this is controlled
146 * in cpu control register 1 in the lower 4 bits.
148 tmp = sgimc->cpuctrl1;
151 sgimc->cpuctrl1 = tmp;
153 /* Step 4: Initialize the RPSS divider register to run as fast
154 * as it can correctly operate. The register is laid
157 * ----------------------------------------
158 * | RESERVED | INCREMENT | DIVIDER |
159 * ----------------------------------------
162 * DIVIDER determines how often a 'tick' happens,
163 * INCREMENT determines by how the RPSS increment
164 * registers value increases at each 'tick'. Thus,
165 * for IP22 we get INCREMENT=1, DIVIDER=1 == 0x101
167 sgimc->divider = 0x101;
169 /* Step 5: Initialize GIO64 arbitrator configuration register.
171 * NOTE: HPC init code in sgihpc_init() must run before us because
172 * we need to know Guiness vs. FullHouse and the board
173 * revision on this machine. You have been warned.
176 /* First the basic invariants across all GIO64 implementations. */
177 tmp = SGIMC_GIOPAR_HPC64; /* All 1st HPC's interface at 64bits */
178 tmp |= SGIMC_GIOPAR_ONEBUS; /* Only one physical GIO bus exists */
180 if (ip22_is_fullhouse()) {
181 /* Fullhouse specific settings. */
182 if (SGIOC_SYSID_BOARDREV(sgioc->sysid) < 2) {
183 tmp |= SGIMC_GIOPAR_HPC264; /* 2nd HPC at 64bits */
184 tmp |= SGIMC_GIOPAR_PLINEEXP0; /* exp0 pipelines */
185 tmp |= SGIMC_GIOPAR_MASTEREXP1; /* exp1 masters */
186 tmp |= SGIMC_GIOPAR_RTIMEEXP0; /* exp0 is realtime */
188 tmp |= SGIMC_GIOPAR_HPC264; /* 2nd HPC 64bits */
189 tmp |= SGIMC_GIOPAR_PLINEEXP0; /* exp[01] pipelined */
190 tmp |= SGIMC_GIOPAR_PLINEEXP1;
191 tmp |= SGIMC_GIOPAR_MASTEREISA; /* EISA masters */
192 tmp |= SGIMC_GIOPAR_GFX64; /* GFX at 64 bits */
195 /* Guiness specific settings. */
196 tmp |= SGIMC_GIOPAR_EISA64; /* MC talks to EISA at 64bits */
197 tmp |= SGIMC_GIOPAR_MASTEREISA; /* EISA bus can act as master */
199 sgimc->giopar = tmp; /* poof */
204 void __init prom_meminit(void) {}
205 void __init prom_free_prom_memory(void)