diff options
Diffstat (limited to 'hw/ssi/npcm_pspi.c')
| -rw-r--r-- | hw/ssi/npcm_pspi.c | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/hw/ssi/npcm_pspi.c b/hw/ssi/npcm_pspi.c new file mode 100644 index 0000000000..3fb935043a --- /dev/null +++ b/hw/ssi/npcm_pspi.c @@ -0,0 +1,221 @@ +/* + * Nuvoton NPCM Peripheral SPI Module (PSPI) + * + * Copyright 2023 Google LLC + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * for more details. + */ + +#include "qemu/osdep.h" + +#include "hw/irq.h" +#include "hw/registerfields.h" +#include "hw/ssi/npcm_pspi.h" +#include "migration/vmstate.h" +#include "qapi/error.h" +#include "qemu/error-report.h" +#include "qemu/log.h" +#include "qemu/module.h" +#include "qemu/units.h" + +#include "trace.h" + +REG16(PSPI_DATA, 0x0) +REG16(PSPI_CTL1, 0x2) + FIELD(PSPI_CTL1, SPIEN, 0, 1) + FIELD(PSPI_CTL1, MOD, 2, 1) + FIELD(PSPI_CTL1, EIR, 5, 1) + FIELD(PSPI_CTL1, EIW, 6, 1) + FIELD(PSPI_CTL1, SCM, 7, 1) + FIELD(PSPI_CTL1, SCIDL, 8, 1) + FIELD(PSPI_CTL1, SCDV, 9, 7) +REG16(PSPI_STAT, 0x4) + FIELD(PSPI_STAT, BSY, 0, 1) + FIELD(PSPI_STAT, RBF, 1, 1) + +static void npcm_pspi_update_irq(NPCMPSPIState *s) +{ + int level = 0; + + /* Only fire IRQ when the module is enabled. */ + if (FIELD_EX16(s->regs[R_PSPI_CTL1], PSPI_CTL1, SPIEN)) { + /* Update interrupt as BSY is cleared. */ + if ((!FIELD_EX16(s->regs[R_PSPI_STAT], PSPI_STAT, BSY)) && + FIELD_EX16(s->regs[R_PSPI_CTL1], PSPI_CTL1, EIW)) { + level = 1; + } + + /* Update interrupt as RBF is set. */ + if (FIELD_EX16(s->regs[R_PSPI_STAT], PSPI_STAT, RBF) && + FIELD_EX16(s->regs[R_PSPI_CTL1], PSPI_CTL1, EIR)) { + level = 1; + } + } + qemu_set_irq(s->irq, level); +} + +static uint16_t npcm_pspi_read_data(NPCMPSPIState *s) +{ + uint16_t value = s->regs[R_PSPI_DATA]; + + /* Clear stat bits as the value are read out. */ + s->regs[R_PSPI_STAT] = 0; + + return value; +} + +static void npcm_pspi_write_data(NPCMPSPIState *s, uint16_t data) +{ + uint16_t value = 0; + + if (FIELD_EX16(s->regs[R_PSPI_CTL1], PSPI_CTL1, MOD)) { + value = ssi_transfer(s->spi, extract16(data, 8, 8)) << 8; + } + value |= ssi_transfer(s->spi, extract16(data, 0, 8)); + s->regs[R_PSPI_DATA] = value; + + /* Mark data as available */ + s->regs[R_PSPI_STAT] = R_PSPI_STAT_BSY_MASK | R_PSPI_STAT_RBF_MASK; +} + +/* Control register read handler. */ +static uint64_t npcm_pspi_ctrl_read(void *opaque, hwaddr addr, + unsigned int size) +{ + NPCMPSPIState *s = opaque; + uint16_t value; + + switch (addr) { + case A_PSPI_DATA: + value = npcm_pspi_read_data(s); + break; + + case A_PSPI_CTL1: + value = s->regs[R_PSPI_CTL1]; + break; + + case A_PSPI_STAT: + value = s->regs[R_PSPI_STAT]; + break; + + default: + qemu_log_mask(LOG_GUEST_ERROR, + "%s: write to invalid offset 0x%" PRIx64 "\n", + DEVICE(s)->canonical_path, addr); + return 0; + } + trace_npcm_pspi_ctrl_read(DEVICE(s)->canonical_path, addr, value); + npcm_pspi_update_irq(s); + + return value; +} + +/* Control register write handler. */ +static void npcm_pspi_ctrl_write(void *opaque, hwaddr addr, uint64_t v, + unsigned int size) +{ + NPCMPSPIState *s = opaque; + uint16_t value = v; + + trace_npcm_pspi_ctrl_write(DEVICE(s)->canonical_path, addr, value); + + switch (addr) { + case A_PSPI_DATA: + npcm_pspi_write_data(s, value); + break; + + case A_PSPI_CTL1: + s->regs[R_PSPI_CTL1] = value; + break; + + case A_PSPI_STAT: + qemu_log_mask(LOG_GUEST_ERROR, + "%s: write to read-only register PSPI_STAT: 0x%08" + PRIx64 "\n", DEVICE(s)->canonical_path, v); + break; + + default: + qemu_log_mask(LOG_GUEST_ERROR, + "%s: write to invalid offset 0x%" PRIx64 "\n", + DEVICE(s)->canonical_path, addr); + return; + } + npcm_pspi_update_irq(s); +} + +static const MemoryRegionOps npcm_pspi_ctrl_ops = { + .read = npcm_pspi_ctrl_read, + .write = npcm_pspi_ctrl_write, + .endianness = DEVICE_LITTLE_ENDIAN, + .valid = { + .min_access_size = 1, + .max_access_size = 2, + .unaligned = false, + }, + .impl = { + .min_access_size = 2, + .max_access_size = 2, + .unaligned = false, + }, +}; + +static void npcm_pspi_enter_reset(Object *obj, ResetType type) +{ + NPCMPSPIState *s = NPCM_PSPI(obj); + + trace_npcm_pspi_enter_reset(DEVICE(obj)->canonical_path, type); + memset(s->regs, 0, sizeof(s->regs)); +} + +static void npcm_pspi_realize(DeviceState *dev, Error **errp) +{ + NPCMPSPIState *s = NPCM_PSPI(dev); + SysBusDevice *sbd = SYS_BUS_DEVICE(dev); + Object *obj = OBJECT(dev); + + s->spi = ssi_create_bus(dev, "pspi"); + memory_region_init_io(&s->mmio, obj, &npcm_pspi_ctrl_ops, s, + "mmio", 4 * KiB); + sysbus_init_mmio(sbd, &s->mmio); + sysbus_init_irq(sbd, &s->irq); +} + +static const VMStateDescription vmstate_npcm_pspi = { + .name = "npcm-pspi", + .version_id = 0, + .minimum_version_id = 0, + .fields = (VMStateField[]) { + VMSTATE_UINT16_ARRAY(regs, NPCMPSPIState, NPCM_PSPI_NR_REGS), + VMSTATE_END_OF_LIST(), + }, +}; + + +static void npcm_pspi_class_init(ObjectClass *klass, void *data) +{ + ResettableClass *rc = RESETTABLE_CLASS(klass); + DeviceClass *dc = DEVICE_CLASS(klass); + + dc->desc = "NPCM Peripheral SPI Module"; + dc->realize = npcm_pspi_realize; + dc->vmsd = &vmstate_npcm_pspi; + rc->phases.enter = npcm_pspi_enter_reset; +} + +static const TypeInfo npcm_pspi_types[] = { + { + .name = TYPE_NPCM_PSPI, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(NPCMPSPIState), + .class_init = npcm_pspi_class_init, + }, +}; +DEFINE_TYPES(npcm_pspi_types); |