1 /* 2 * (C) Copyright 2000-2002 3 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4 * 5 * SPDX-License-Identifier: GPL-2.0+ 6 */ 7 8 #include <common.h> 9 #include <mpc8xx.h> 10 #include <mpc8xx_irq.h> 11 #include <asm/processor.h> 12 #include <asm/io.h> 13 #include <commproc.h> 14 15 /************************************************************************/ 16 17 /* 18 * CPM interrupt vector functions. 19 */ 20 struct interrupt_action { 21 interrupt_handler_t *handler; 22 void *arg; 23 }; 24 25 static struct interrupt_action cpm_vecs[CPMVEC_NR]; 26 static struct interrupt_action irq_vecs[NR_IRQS]; 27 28 static void cpm_interrupt_init(void); 29 static void cpm_interrupt(void *regs); 30 31 /************************************************************************/ 32 33 int interrupt_init_cpu(unsigned *decrementer_count) 34 { 35 immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR; 36 37 *decrementer_count = get_tbclk() / CONFIG_SYS_HZ; 38 39 /* disable all interrupts */ 40 out_be32(&immr->im_siu_conf.sc_simask, 0); 41 42 /* Configure CPM interrupts */ 43 cpm_interrupt_init(); 44 45 return 0; 46 } 47 48 /************************************************************************/ 49 50 /* 51 * Handle external interrupts 52 */ 53 void external_interrupt(struct pt_regs *regs) 54 { 55 immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR; 56 int irq; 57 ulong simask; 58 ulong vec, v_bit; 59 60 /* 61 * read the SIVEC register and shift the bits down 62 * to get the irq number 63 */ 64 vec = in_be32(&immr->im_siu_conf.sc_sivec); 65 irq = vec >> 26; 66 v_bit = 0x80000000UL >> irq; 67 68 /* 69 * Read Interrupt Mask Register and Mask Interrupts 70 */ 71 simask = in_be32(&immr->im_siu_conf.sc_simask); 72 clrbits_be32(&immr->im_siu_conf.sc_simask, 0xFFFF0000 >> irq); 73 74 if (!(irq & 0x1)) { /* External Interrupt ? */ 75 ulong siel; 76 77 /* 78 * Read Interrupt Edge/Level Register 79 */ 80 siel = in_be32(&immr->im_siu_conf.sc_siel); 81 82 if (siel & v_bit) { /* edge triggered interrupt ? */ 83 /* 84 * Rewrite SIPEND Register to clear interrupt 85 */ 86 out_be32(&immr->im_siu_conf.sc_sipend, v_bit); 87 } 88 } 89 90 if (irq_vecs[irq].handler != NULL) { 91 irq_vecs[irq].handler(irq_vecs[irq].arg); 92 } else { 93 printf("\nBogus External Interrupt IRQ %d Vector %ld\n", 94 irq, vec); 95 /* turn off the bogus interrupt to avoid it from now */ 96 simask &= ~v_bit; 97 } 98 /* 99 * Re-Enable old Interrupt Mask 100 */ 101 out_be32(&immr->im_siu_conf.sc_simask, simask); 102 } 103 104 /************************************************************************/ 105 106 /* 107 * CPM interrupt handler 108 */ 109 static void cpm_interrupt(void *regs) 110 { 111 immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR; 112 uint vec; 113 114 /* 115 * Get the vector by setting the ACK bit 116 * and then reading the register. 117 */ 118 out_be16(&immr->im_cpic.cpic_civr, 1); 119 vec = in_be16(&immr->im_cpic.cpic_civr); 120 vec >>= 11; 121 122 if (cpm_vecs[vec].handler != NULL) { 123 (*cpm_vecs[vec].handler) (cpm_vecs[vec].arg); 124 } else { 125 clrbits_be32(&immr->im_cpic.cpic_cimr, 1 << vec); 126 printf("Masking bogus CPM interrupt vector 0x%x\n", vec); 127 } 128 /* 129 * After servicing the interrupt, 130 * we have to remove the status indicator. 131 */ 132 setbits_be32(&immr->im_cpic.cpic_cisr, 1 << vec); 133 } 134 135 /* 136 * The CPM can generate the error interrupt when there is a race 137 * condition between generating and masking interrupts. All we have 138 * to do is ACK it and return. This is a no-op function so we don't 139 * need any special tests in the interrupt handler. 140 */ 141 static void cpm_error_interrupt(void *dummy) 142 { 143 } 144 145 /************************************************************************/ 146 /* 147 * Install and free an interrupt handler 148 */ 149 void irq_install_handler(int vec, interrupt_handler_t *handler, void *arg) 150 { 151 immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR; 152 153 if ((vec & CPMVEC_OFFSET) != 0) { 154 /* CPM interrupt */ 155 vec &= 0xffff; 156 if (cpm_vecs[vec].handler != NULL) 157 printf("CPM interrupt 0x%x replacing 0x%x\n", 158 (uint)handler, (uint)cpm_vecs[vec].handler); 159 cpm_vecs[vec].handler = handler; 160 cpm_vecs[vec].arg = arg; 161 setbits_be32(&immr->im_cpic.cpic_cimr, 1 << vec); 162 } else { 163 /* SIU interrupt */ 164 if (irq_vecs[vec].handler != NULL) 165 printf("SIU interrupt %d 0x%x replacing 0x%x\n", 166 vec, (uint)handler, (uint)cpm_vecs[vec].handler); 167 irq_vecs[vec].handler = handler; 168 irq_vecs[vec].arg = arg; 169 setbits_be32(&immr->im_siu_conf.sc_simask, 1 << (31 - vec)); 170 } 171 } 172 173 void irq_free_handler(int vec) 174 { 175 immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR; 176 177 if ((vec & CPMVEC_OFFSET) != 0) { 178 /* CPM interrupt */ 179 vec &= 0xffff; 180 clrbits_be32(&immr->im_cpic.cpic_cimr, 1 << vec); 181 cpm_vecs[vec].handler = NULL; 182 cpm_vecs[vec].arg = NULL; 183 } else { 184 /* SIU interrupt */ 185 clrbits_be32(&immr->im_siu_conf.sc_simask, 1 << (31 - vec)); 186 irq_vecs[vec].handler = NULL; 187 irq_vecs[vec].arg = NULL; 188 } 189 } 190 191 /************************************************************************/ 192 193 static void cpm_interrupt_init(void) 194 { 195 immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR; 196 uint cicr; 197 198 /* 199 * Initialize the CPM interrupt controller. 200 */ 201 202 cicr = CICR_SCD_SCC4 | CICR_SCC_SCC3 | CICR_SCB_SCC2 | CICR_SCA_SCC1 | 203 ((CPM_INTERRUPT / 2) << 13) | CICR_HP_MASK; 204 205 out_be32(&immr->im_cpic.cpic_cicr, cicr); 206 out_be32(&immr->im_cpic.cpic_cimr, 0); 207 208 /* 209 * Install the error handler. 210 */ 211 irq_install_handler(CPMVEC_ERROR, cpm_error_interrupt, NULL); 212 213 setbits_be32(&immr->im_cpic.cpic_cicr, CICR_IEN); 214 215 /* 216 * Install the cpm interrupt handler 217 */ 218 irq_install_handler(CPM_INTERRUPT, cpm_interrupt, NULL); 219 } 220 221 /************************************************************************/ 222 223 /* 224 * timer_interrupt - gets called when the decrementer overflows, 225 * with interrupts disabled. 226 * Trivial implementation - no need to be really accurate. 227 */ 228 void timer_interrupt_cpu(struct pt_regs *regs) 229 { 230 immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR; 231 232 /* Reset Timer Expired and Timers Interrupt Status */ 233 out_be32(&immr->im_clkrstk.cark_plprcrk, KAPWR_KEY); 234 __asm__ ("nop"); 235 /* 236 Clear TEXPS (and TMIST on older chips). SPLSS (on older 237 chips) is cleared too. 238 239 Bitwise OR is a read-modify-write operation so ALL bits 240 which are cleared by writing `1' would be cleared by 241 operations like 242 243 immr->im_clkrst.car_plprcr |= PLPRCR_TEXPS; 244 245 The same can be achieved by simple writing of the PLPRCR 246 to itself. If a bit value should be preserved, read the 247 register, ZERO the bit and write, not OR, the result back. 248 */ 249 setbits_be32(&immr->im_clkrst.car_plprcr, 0); 250 } 251 252 /************************************************************************/ 253