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/cpm_8xx.h> 12 #include <asm/processor.h> 13 #include <asm/io.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 void 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 46 /************************************************************************/ 47 48 /* 49 * Handle external interrupts 50 */ 51 void external_interrupt(struct pt_regs *regs) 52 { 53 immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR; 54 int irq; 55 ulong simask; 56 ulong vec, v_bit; 57 58 /* 59 * read the SIVEC register and shift the bits down 60 * to get the irq number 61 */ 62 vec = in_be32(&immr->im_siu_conf.sc_sivec); 63 irq = vec >> 26; 64 v_bit = 0x80000000UL >> irq; 65 66 /* 67 * Read Interrupt Mask Register and Mask Interrupts 68 */ 69 simask = in_be32(&immr->im_siu_conf.sc_simask); 70 clrbits_be32(&immr->im_siu_conf.sc_simask, 0xFFFF0000 >> irq); 71 72 if (!(irq & 0x1)) { /* External Interrupt ? */ 73 ulong siel; 74 75 /* 76 * Read Interrupt Edge/Level Register 77 */ 78 siel = in_be32(&immr->im_siu_conf.sc_siel); 79 80 if (siel & v_bit) { /* edge triggered interrupt ? */ 81 /* 82 * Rewrite SIPEND Register to clear interrupt 83 */ 84 out_be32(&immr->im_siu_conf.sc_sipend, v_bit); 85 } 86 } 87 88 if (irq_vecs[irq].handler != NULL) { 89 irq_vecs[irq].handler(irq_vecs[irq].arg); 90 } else { 91 printf("\nBogus External Interrupt IRQ %d Vector %ld\n", 92 irq, vec); 93 /* turn off the bogus interrupt to avoid it from now */ 94 simask &= ~v_bit; 95 } 96 /* 97 * Re-Enable old Interrupt Mask 98 */ 99 out_be32(&immr->im_siu_conf.sc_simask, simask); 100 } 101 102 /************************************************************************/ 103 104 /* 105 * CPM interrupt handler 106 */ 107 static void cpm_interrupt(void *regs) 108 { 109 immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR; 110 uint vec; 111 112 /* 113 * Get the vector by setting the ACK bit 114 * and then reading the register. 115 */ 116 out_be16(&immr->im_cpic.cpic_civr, 1); 117 vec = in_be16(&immr->im_cpic.cpic_civr); 118 vec >>= 11; 119 120 if (cpm_vecs[vec].handler != NULL) { 121 (*cpm_vecs[vec].handler) (cpm_vecs[vec].arg); 122 } else { 123 clrbits_be32(&immr->im_cpic.cpic_cimr, 1 << vec); 124 printf("Masking bogus CPM interrupt vector 0x%x\n", vec); 125 } 126 /* 127 * After servicing the interrupt, 128 * we have to remove the status indicator. 129 */ 130 setbits_be32(&immr->im_cpic.cpic_cisr, 1 << vec); 131 } 132 133 /* 134 * The CPM can generate the error interrupt when there is a race 135 * condition between generating and masking interrupts. All we have 136 * to do is ACK it and return. This is a no-op function so we don't 137 * need any special tests in the interrupt handler. 138 */ 139 static void cpm_error_interrupt(void *dummy) 140 { 141 } 142 143 /************************************************************************/ 144 /* 145 * Install and free an interrupt handler 146 */ 147 void irq_install_handler(int vec, interrupt_handler_t *handler, void *arg) 148 { 149 immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR; 150 151 if ((vec & CPMVEC_OFFSET) != 0) { 152 /* CPM interrupt */ 153 vec &= 0xffff; 154 if (cpm_vecs[vec].handler != NULL) 155 printf("CPM interrupt 0x%x replacing 0x%x\n", 156 (uint)handler, (uint)cpm_vecs[vec].handler); 157 cpm_vecs[vec].handler = handler; 158 cpm_vecs[vec].arg = arg; 159 setbits_be32(&immr->im_cpic.cpic_cimr, 1 << vec); 160 } else { 161 /* SIU interrupt */ 162 if (irq_vecs[vec].handler != NULL) 163 printf("SIU interrupt %d 0x%x replacing 0x%x\n", 164 vec, (uint)handler, (uint)cpm_vecs[vec].handler); 165 irq_vecs[vec].handler = handler; 166 irq_vecs[vec].arg = arg; 167 setbits_be32(&immr->im_siu_conf.sc_simask, 1 << (31 - vec)); 168 } 169 } 170 171 void irq_free_handler(int vec) 172 { 173 immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR; 174 175 if ((vec & CPMVEC_OFFSET) != 0) { 176 /* CPM interrupt */ 177 vec &= 0xffff; 178 clrbits_be32(&immr->im_cpic.cpic_cimr, 1 << vec); 179 cpm_vecs[vec].handler = NULL; 180 cpm_vecs[vec].arg = NULL; 181 } else { 182 /* SIU interrupt */ 183 clrbits_be32(&immr->im_siu_conf.sc_simask, 1 << (31 - vec)); 184 irq_vecs[vec].handler = NULL; 185 irq_vecs[vec].arg = NULL; 186 } 187 } 188 189 /************************************************************************/ 190 191 static void cpm_interrupt_init(void) 192 { 193 immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR; 194 uint cicr; 195 196 /* 197 * Initialize the CPM interrupt controller. 198 */ 199 200 cicr = CICR_SCD_SCC4 | CICR_SCC_SCC3 | CICR_SCB_SCC2 | CICR_SCA_SCC1 | 201 ((CPM_INTERRUPT / 2) << 13) | CICR_HP_MASK; 202 203 out_be32(&immr->im_cpic.cpic_cicr, cicr); 204 out_be32(&immr->im_cpic.cpic_cimr, 0); 205 206 /* 207 * Install the error handler. 208 */ 209 irq_install_handler(CPMVEC_ERROR, cpm_error_interrupt, NULL); 210 211 setbits_be32(&immr->im_cpic.cpic_cicr, CICR_IEN); 212 213 /* 214 * Install the cpm interrupt handler 215 */ 216 irq_install_handler(CPM_INTERRUPT, cpm_interrupt, NULL); 217 } 218 219 /************************************************************************/ 220 221 /* 222 * timer_interrupt - gets called when the decrementer overflows, 223 * with interrupts disabled. 224 * Trivial implementation - no need to be really accurate. 225 */ 226 void timer_interrupt_cpu(struct pt_regs *regs) 227 { 228 immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR; 229 230 /* Reset Timer Expired and Timers Interrupt Status */ 231 out_be32(&immr->im_clkrstk.cark_plprcrk, KAPWR_KEY); 232 __asm__ ("nop"); 233 /* 234 Clear TEXPS (and TMIST on older chips). SPLSS (on older 235 chips) is cleared too. 236 237 Bitwise OR is a read-modify-write operation so ALL bits 238 which are cleared by writing `1' would be cleared by 239 operations like 240 241 immr->im_clkrst.car_plprcr |= PLPRCR_TEXPS; 242 243 The same can be achieved by simple writing of the PLPRCR 244 to itself. If a bit value should be preserved, read the 245 register, ZERO the bit and write, not OR, the result back. 246 */ 247 setbits_be32(&immr->im_clkrst.car_plprcr, 0); 248 } 249 250 /************************************************************************/ 251