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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 | /* tadpole.c: Probing for the tadpole clock stopping h/w at boot time. * * Copyright (C) 1996 David Redman (djhr@tadpole.co.uk) */ #include <linux/string.h> #include <linux/kernel.h> #include <linux/sched.h> #include <linux/init.h> #include <asm/asi.h> #include <asm/oplib.h> #include <asm/io.h> #define MACIO_SCSI_CSR_ADDR 0x78400000 #define MACIO_EN_DMA 0x00000200 #define CLOCK_INIT_DONE 1 static int clk_state; static volatile unsigned char *clk_ctrl; void (*cpu_pwr_save)(void); static inline unsigned int ldphys(unsigned int addr) { unsigned long data; __asm__ __volatile__("\n\tlda [%1] %2, %0\n\t" : "=r" (data) : "r" (addr), "i" (ASI_M_BYPASS)); return data; } static void clk_init(void) { __asm__ __volatile__("mov 0x6c, %%g1\n\t" "mov 0x4c, %%g2\n\t" "mov 0xdf, %%g3\n\t" "stb %%g1, [%0+3]\n\t" "stb %%g2, [%0+3]\n\t" "stb %%g3, [%0+3]\n\t" : : "r" (clk_ctrl) : "g1", "g2", "g3"); } static void clk_slow(void) { __asm__ __volatile__("mov 0xcc, %%g2\n\t" "mov 0x4c, %%g3\n\t" "mov 0xcf, %%g4\n\t" "mov 0xdf, %%g5\n\t" "stb %%g2, [%0+3]\n\t" "stb %%g3, [%0+3]\n\t" "stb %%g4, [%0+3]\n\t" "stb %%g5, [%0+3]\n\t" : : "r" (clk_ctrl) : "g2", "g3", "g4", "g5"); } /* * Tadpole is guaranteed to be UP, using local_irq_save. */ static void tsu_clockstop(void) { unsigned int mcsr; unsigned long flags; if (!clk_ctrl) return; if (!(clk_state & CLOCK_INIT_DONE)) { local_irq_save(flags); clk_init(); clk_state |= CLOCK_INIT_DONE; /* all done */ local_irq_restore(flags); return; } if (!(clk_ctrl[2] & 1)) return; /* no speed up yet */ local_irq_save(flags); /* if SCSI DMA in progress, don't slow clock */ mcsr = ldphys(MACIO_SCSI_CSR_ADDR); if ((mcsr&MACIO_EN_DMA) != 0) { local_irq_restore(flags); return; } /* TODO... the minimum clock setting ought to increase the * memory refresh interval.. */ clk_slow(); local_irq_restore(flags); } static void swift_clockstop(void) { if (!clk_ctrl) return; clk_ctrl[0] = 0; } void __init clock_stop_probe(void) { unsigned int node, clk_nd; char name[20]; prom_getstring(prom_root_node, "name", name, sizeof(name)); if (strncmp(name, "Tadpole", 7)) return; node = prom_getchild(prom_root_node); node = prom_searchsiblings(node, "obio"); node = prom_getchild(node); clk_nd = prom_searchsiblings(node, "clk-ctrl"); if (!clk_nd) return; printk("Clock Stopping h/w detected... "); clk_ctrl = (char *) prom_getint(clk_nd, "address"); clk_state = 0; if (name[10] == '\0') { cpu_pwr_save = tsu_clockstop; printk("enabled (S3)\n"); } else if ((name[10] == 'X') || (name[10] == 'G')) { cpu_pwr_save = swift_clockstop; printk("enabled (%s)\n",name+7); } else printk("disabled %s\n",name+7); } |