hw/ppc/spapr_irq.c

   1 /*
   2  * QEMU PowerPC sPAPR IRQ interface
   3  *
   4  * Copyright (c) 2018, IBM Corporation.
   5  *
   6  * This code is licensed under the GPL version 2 or later. See the
   7  * COPYING file in the top-level directory.
   8  */
   9
  10 #include "qemu/osdep.h"
  11 #include "qemu/log.h"
  12 #include "qemu/error-report.h"
  13 #include "qapi/error.h"
  14 #include "hw/ppc/spapr.h"
  15 #include "hw/ppc/xics.h"
  16
  17 void spapr_irq_msi_init(sPAPRMachineState *spapr, uint32_t nr_msis)
  18 {
  19     spapr->irq_map_nr = nr_msis;
  20     spapr->irq_map = bitmap_new(spapr->irq_map_nr);
  21 }
  22
  23 int spapr_irq_msi_alloc(sPAPRMachineState *spapr, uint32_t num, bool align,
  24                         Error **errp)
  25 {
  26     int irq;
  27
  28     /*
  29      * The 'align_mask' parameter of bitmap_find_next_zero_area()
  30      * should be one less than a power of 2; 0 means no
  31      * alignment. Adapt the 'align' value of the former allocator
  32      * to fit the requirements of bitmap_find_next_zero_area()
  33      */
  34     align -= 1;
  35
  36     irq = bitmap_find_next_zero_area(spapr->irq_map, spapr->irq_map_nr, 0, num,
  37                                      align);
  38     if (irq == spapr->irq_map_nr) {
  39         error_setg(errp, "can't find a free %d-IRQ block", num);
  40         return -1;
  41     }
  42
  43     bitmap_set(spapr->irq_map, irq, num);
  44
  45     return irq + SPAPR_IRQ_MSI;
  46 }
  47
  48 void spapr_irq_msi_free(sPAPRMachineState *spapr, int irq, uint32_t num)
  49 {
  50     bitmap_clear(spapr->irq_map, irq - SPAPR_IRQ_MSI, num);
  51 }
  52
  53 void spapr_irq_msi_reset(sPAPRMachineState *spapr)
  54 {
  55     bitmap_clear(spapr->irq_map, 0, spapr->irq_map_nr);
  56 }