Author: neel Date: Wed Dec 17 03:04:43 2014 New Revision: 275850 URL: https://svnweb.freebsd.org/changeset/base/275850
Log: Fix 8259 IRQ priority resolver. Initialize the 8259 such that IRQ7 is the lowest priority. Reviewed by: tychon Differential Revision: https://reviews.freebsd.org/D1322 MFC after: 1 week Modified: head/sys/amd64/vmm/io/vatpic.c Modified: head/sys/amd64/vmm/io/vatpic.c ============================================================================== --- head/sys/amd64/vmm/io/vatpic.c Wed Dec 17 01:48:32 2014 (r275849) +++ head/sys/amd64/vmm/io/vatpic.c Wed Dec 17 03:04:43 2014 (r275850) @@ -75,7 +75,7 @@ struct atpic { uint8_t mask; /* Interrupt Mask Register (IMR) */ int acnt[8]; /* sum of pin asserts and deasserts */ - int priority; /* current pin priority */ + int lowprio; /* lowest priority irq */ bool intr_raised; }; @@ -102,6 +102,14 @@ struct vatpic { #define VATPIC_CTR4(vatpic, fmt, a1, a2, a3, a4) \ VM_CTR4((vatpic)->vm, fmt, a1, a2, a3, a4) +/* + * Loop over all the pins in priority order from highest to lowest. + */ +#define ATPIC_PIN_FOREACH(pinvar, atpic, tmpvar) \ + for (tmpvar = 0, pinvar = (atpic->lowprio + 1) & 0x7; \ + tmpvar < 8; \ + tmpvar++, pinvar = (pinvar + 1) & 0x7) + static void vatpic_set_pinstate(struct vatpic *vatpic, int pin, bool newstate); static __inline int @@ -110,8 +118,7 @@ vatpic_get_highest_isrpin(struct atpic * int bit, pin; int i; - for (i = 0; i <= 7; i++) { - pin = ((i + 7 - atpic->priority) & 0x7); + ATPIC_PIN_FOREACH(pin, atpic, i) { bit = (1 << pin); if (atpic->service & bit) @@ -125,8 +132,7 @@ static __inline int vatpic_get_highest_irrpin(struct atpic *atpic) { int serviced; - int bit, pin; - int i, j; + int bit, pin, tmp; /* * In 'Special Fully-Nested Mode' when an interrupt request from @@ -137,17 +143,21 @@ vatpic_get_highest_irrpin(struct atpic * if (atpic->sfn) serviced &= ~(1 << 2); - for (i = 0; i <= 7; i++) { - pin = ((i + 7 - atpic->priority) & 0x7); - bit = (1 << pin); - if (serviced & bit) + ATPIC_PIN_FOREACH(pin, atpic, tmp) { + bit = 1 << pin; + + /* + * If there is already an interrupt in service at the same + * or higher priority then bail. + */ + if ((serviced & bit) != 0) break; - } - for (j = 0; j < i; j++) { - pin = ((j + 7 - atpic->priority) & 0x7); - bit = (1 << pin); - if (atpic->request & bit && (~atpic->mask & bit)) + /* + * If an interrupt is asserted and not masked then return + * the corresponding 'pin' to the caller. + */ + if ((atpic->request & bit) != 0 && (atpic->mask & bit) == 0) return (pin); } @@ -238,7 +248,7 @@ vatpic_icw1(struct vatpic *vatpic, struc atpic->icw_num = 1; atpic->mask = 0; - atpic->priority = 0; + atpic->lowprio = 7; atpic->rd_cmd_reg = 0; if ((val & ICW1_SNGL) != 0) { @@ -329,11 +339,11 @@ vatpic_ocw2(struct vatpic *vatpic, struc atpic->service &= ~(1 << isr_bit); if (atpic->rotate) - atpic->priority = isr_bit; + atpic->lowprio = isr_bit; } } else if ((val & OCW2_SL) != 0 && atpic->rotate == true) { /* specific priority */ - atpic->priority = val & 0x7; + atpic->lowprio = val & 0x7; } return (0); @@ -530,7 +540,7 @@ vatpic_pin_accepted(struct atpic *atpic, if (atpic->aeoi == true) { if (atpic->rotate == true) - atpic->priority = pin; + atpic->lowprio = pin; } else { atpic->service |= (1 << pin); } _______________________________________________ svn-src-all@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
