From 97398d900caaccbf1b6cc53a80581b69687757e7 Mon Sep 17 00:00:00 2001 From: Andrew Baumann Date: Wed, 16 Mar 2016 17:06:01 +0000 Subject: [PATCH] bcm2835_aux: add emulation of BCM2835 AUX (aka UART1) block At present only the core UART functions (data path for tx/rx) are implemented, which is enough for UEFI to boot. The following features/registers are unimplemented: * Line/modem control * Scratch register * Extra control * Baudrate * SPI interfaces Signed-off-by: Andrew Baumann Reviewed-by: Peter Maydell Message-id: 1457467526-8840-3-git-send-email-Andrew.Baumann@microsoft.com Signed-off-by: Peter Maydell --- hw/arm/bcm2835_peripherals.c | 32 ++++ hw/char/Makefile.objs | 1 + hw/char/bcm2835_aux.c | 316 +++++++++++++++++++++++++++++++++++ include/hw/arm/bcm2835_peripherals.h | 2 + include/hw/char/bcm2835_aux.h | 33 ++++ 5 files changed, 384 insertions(+) create mode 100644 hw/char/bcm2835_aux.c create mode 100644 include/hw/char/bcm2835_aux.h diff --git a/hw/arm/bcm2835_peripherals.c b/hw/arm/bcm2835_peripherals.c index 6ce9cd1..d6453cc 100644 --- a/hw/arm/bcm2835_peripherals.c +++ b/hw/arm/bcm2835_peripherals.c @@ -12,6 +12,7 @@ #include "hw/arm/bcm2835_peripherals.h" #include "hw/misc/bcm2835_mbox_defs.h" #include "hw/arm/raspi_platform.h" +#include "sysemu/char.h" /* Peripheral base address on the VC (GPU) system bus */ #define BCM2835_VC_PERI_BASE 0x7e000000 @@ -48,6 +49,11 @@ static void bcm2835_peripherals_init(Object *obj) object_property_add_child(obj, "uart0", OBJECT(s->uart0), NULL); qdev_set_parent_bus(DEVICE(s->uart0), sysbus_get_default()); + /* AUX / UART1 */ + object_initialize(&s->aux, sizeof(s->aux), TYPE_BCM2835_AUX); + object_property_add_child(obj, "aux", OBJECT(&s->aux), NULL); + qdev_set_parent_bus(DEVICE(&s->aux), sysbus_get_default()); + /* Mailboxes */ object_initialize(&s->mboxes, sizeof(s->mboxes), TYPE_BCM2835_MBOX); object_property_add_child(obj, "mbox", OBJECT(&s->mboxes), NULL); @@ -79,6 +85,7 @@ static void bcm2835_peripherals_realize(DeviceState *dev, Error **errp) MemoryRegion *ram; Error *err = NULL; uint32_t ram_size; + CharDriverState *chr; int n; obj = object_property_get_link(OBJECT(dev), "ram", &err); @@ -131,6 +138,29 @@ static void bcm2835_peripherals_realize(DeviceState *dev, Error **errp) qdev_get_gpio_in_named(DEVICE(&s->ic), BCM2835_IC_GPU_IRQ, INTERRUPT_UART)); + /* AUX / UART1 */ + /* TODO: don't call qemu_char_get_next_serial() here, instead set + * chardev properties for each uart at the board level, once pl011 + * (uart0) has been updated to avoid qemu_char_get_next_serial() + */ + chr = qemu_char_get_next_serial(); + if (chr == NULL) { + chr = qemu_chr_new("bcm2835.uart1", "null", NULL); + } + qdev_prop_set_chr(DEVICE(&s->aux), "chardev", chr); + + object_property_set_bool(OBJECT(&s->aux), true, "realized", &err); + if (err) { + error_propagate(errp, err); + return; + } + + memory_region_add_subregion(&s->peri_mr, UART1_OFFSET, + sysbus_mmio_get_region(SYS_BUS_DEVICE(&s->aux), 0)); + sysbus_connect_irq(SYS_BUS_DEVICE(&s->aux), 0, + qdev_get_gpio_in_named(DEVICE(&s->ic), BCM2835_IC_GPU_IRQ, + INTERRUPT_AUX)); + /* Mailboxes */ object_property_set_bool(OBJECT(&s->mboxes), true, "realized", &err); if (err) { @@ -203,6 +233,8 @@ static void bcm2835_peripherals_class_init(ObjectClass *oc, void *data) DeviceClass *dc = DEVICE_CLASS(oc); dc->realize = bcm2835_peripherals_realize; + /* Reason: realize() method uses qemu_char_get_next_serial() */ + dc->cannot_instantiate_with_device_add_yet = true; } static const TypeInfo bcm2835_peripherals_type_info = { diff --git a/hw/char/Makefile.objs b/hw/char/Makefile.objs index 5931cc8..69a553c 100644 --- a/hw/char/Makefile.objs +++ b/hw/char/Makefile.objs @@ -16,6 +16,7 @@ obj-$(CONFIG_SH4) += sh_serial.o obj-$(CONFIG_PSERIES) += spapr_vty.o obj-$(CONFIG_DIGIC) += digic-uart.o obj-$(CONFIG_STM32F2XX_USART) += stm32f2xx_usart.o +obj-$(CONFIG_RASPI) += bcm2835_aux.o common-obj-$(CONFIG_ETRAXFS) += etraxfs_ser.o common-obj-$(CONFIG_ISA_DEBUG) += debugcon.o diff --git a/hw/char/bcm2835_aux.c b/hw/char/bcm2835_aux.c new file mode 100644 index 0000000..0394d11 --- /dev/null +++ b/hw/char/bcm2835_aux.c @@ -0,0 +1,316 @@ +/* + * BCM2835 (Raspberry Pi / Pi 2) Aux block (mini UART and SPI). + * Copyright (c) 2015, Microsoft + * Written by Andrew Baumann + * Based on pl011.c, copyright terms below: + * + * Arm PrimeCell PL011 UART + * + * Copyright (c) 2006 CodeSourcery. + * Written by Paul Brook + * + * This code is licensed under the GPL. + * + * At present only the core UART functions (data path for tx/rx) are + * implemented. The following features/registers are unimplemented: + * - Line/modem control + * - Scratch register + * - Extra control + * - Baudrate + * - SPI interfaces + */ + +#include "qemu/osdep.h" +#include "hw/char/bcm2835_aux.h" + +#define AUX_IRQ 0x0 +#define AUX_ENABLES 0x4 +#define AUX_MU_IO_REG 0x40 +#define AUX_MU_IER_REG 0x44 +#define AUX_MU_IIR_REG 0x48 +#define AUX_MU_LCR_REG 0x4c +#define AUX_MU_MCR_REG 0x50 +#define AUX_MU_LSR_REG 0x54 +#define AUX_MU_MSR_REG 0x58 +#define AUX_MU_SCRATCH 0x5c +#define AUX_MU_CNTL_REG 0x60 +#define AUX_MU_STAT_REG 0x64 +#define AUX_MU_BAUD_REG 0x68 + +/* bits in IER/IIR registers */ +#define TX_INT 0x1 +#define RX_INT 0x2 + +static void bcm2835_aux_update(BCM2835AuxState *s) +{ + /* signal an interrupt if either: + * 1. rx interrupt is enabled and we have a non-empty rx fifo, or + * 2. the tx interrupt is enabled (since we instantly drain the tx fifo) + */ + s->iir = 0; + if ((s->ier & RX_INT) && s->read_count != 0) { + s->iir |= RX_INT; + } + if (s->ier & TX_INT) { + s->iir |= TX_INT; + } + qemu_set_irq(s->irq, s->iir != 0); +} + +static uint64_t bcm2835_aux_read(void *opaque, hwaddr offset, unsigned size) +{ + BCM2835AuxState *s = opaque; + uint32_t c, res; + + switch (offset) { + case AUX_IRQ: + return s->iir != 0; + + case AUX_ENABLES: + return 1; /* mini UART permanently enabled */ + + case AUX_MU_IO_REG: + /* "DLAB bit set means access baudrate register" is NYI */ + c = s->read_fifo[s->read_pos]; + if (s->read_count > 0) { + s->read_count--; + if (++s->read_pos == BCM2835_AUX_RX_FIFO_LEN) { + s->read_pos = 0; + } + } + if (s->chr) { + qemu_chr_accept_input(s->chr); + } + bcm2835_aux_update(s); + return c; + + case AUX_MU_IER_REG: + /* "DLAB bit set means access baudrate register" is NYI */ + return 0xc0 | s->ier; /* FIFO enables always read 1 */ + + case AUX_MU_IIR_REG: + res = 0xc0; /* FIFO enables */ + /* The spec is unclear on what happens when both tx and rx + * interrupts are active, besides that this cannot occur. At + * present, we choose to prioritise the rx interrupt, since + * the tx fifo is always empty. */ + if (s->read_count != 0) { + res |= 0x4; + } else { + res |= 0x2; + } + if (s->iir == 0) { + res |= 0x1; + } + return res; + + case AUX_MU_LCR_REG: + qemu_log_mask(LOG_UNIMP, "%s: AUX_MU_LCR_REG unsupported\n", __func__); + return 0; + + case AUX_MU_MCR_REG: + qemu_log_mask(LOG_UNIMP, "%s: AUX_MU_MCR_REG unsupported\n", __func__); + return 0; + + case AUX_MU_LSR_REG: + res = 0x60; /* tx idle, empty */ + if (s->read_count != 0) { + res |= 0x1; + } + return res; + + case AUX_MU_MSR_REG: + qemu_log_mask(LOG_UNIMP, "%s: AUX_MU_MSR_REG unsupported\n", __func__); + return 0; + + case AUX_MU_SCRATCH: + qemu_log_mask(LOG_UNIMP, "%s: AUX_MU_SCRATCH unsupported\n", __func__); + return 0; + + case AUX_MU_CNTL_REG: + return 0x3; /* tx, rx enabled */ + + case AUX_MU_STAT_REG: + res = 0x30e; /* space in the output buffer, empty tx fifo, idle tx/rx */ + if (s->read_count > 0) { + res |= 0x1; /* data in input buffer */ + assert(s->read_count < BCM2835_AUX_RX_FIFO_LEN); + res |= ((uint32_t)s->read_count) << 16; /* rx fifo fill level */ + } + return res; + + case AUX_MU_BAUD_REG: + qemu_log_mask(LOG_UNIMP, "%s: AUX_MU_BAUD_REG unsupported\n", __func__); + return 0; + + default: + qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n", + __func__, offset); + return 0; + } +} + +static void bcm2835_aux_write(void *opaque, hwaddr offset, uint64_t value, + unsigned size) +{ + BCM2835AuxState *s = opaque; + unsigned char ch; + + switch (offset) { + case AUX_ENABLES: + if (value != 1) { + qemu_log_mask(LOG_UNIMP, "%s: unsupported attempt to enable SPI " + "or disable UART\n", __func__); + } + break; + + case AUX_MU_IO_REG: + /* "DLAB bit set means access baudrate register" is NYI */ + ch = value; + if (s->chr) { + qemu_chr_fe_write(s->chr, &ch, 1); + } + break; + + case AUX_MU_IER_REG: + /* "DLAB bit set means access baudrate register" is NYI */ + s->ier = value & (TX_INT | RX_INT); + bcm2835_aux_update(s); + break; + + case AUX_MU_IIR_REG: + if (value & 0x2) { + s->read_count = 0; + } + break; + + case AUX_MU_LCR_REG: + qemu_log_mask(LOG_UNIMP, "%s: AUX_MU_LCR_REG unsupported\n", __func__); + break; + + case AUX_MU_MCR_REG: + qemu_log_mask(LOG_UNIMP, "%s: AUX_MU_MCR_REG unsupported\n", __func__); + break; + + case AUX_MU_SCRATCH: + qemu_log_mask(LOG_UNIMP, "%s: AUX_MU_SCRATCH unsupported\n", __func__); + break; + + case AUX_MU_CNTL_REG: + qemu_log_mask(LOG_UNIMP, "%s: AUX_MU_CNTL_REG unsupported\n", __func__); + break; + + case AUX_MU_BAUD_REG: + qemu_log_mask(LOG_UNIMP, "%s: AUX_MU_BAUD_REG unsupported\n", __func__); + break; + + default: + qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n", + __func__, offset); + } + + bcm2835_aux_update(s); +} + +static int bcm2835_aux_can_receive(void *opaque) +{ + BCM2835AuxState *s = opaque; + + return s->read_count < BCM2835_AUX_RX_FIFO_LEN; +} + +static void bcm2835_aux_put_fifo(void *opaque, uint8_t value) +{ + BCM2835AuxState *s = opaque; + int slot; + + slot = s->read_pos + s->read_count; + if (slot >= BCM2835_AUX_RX_FIFO_LEN) { + slot -= BCM2835_AUX_RX_FIFO_LEN; + } + s->read_fifo[slot] = value; + s->read_count++; + if (s->read_count == BCM2835_AUX_RX_FIFO_LEN) { + /* buffer full */ + } + bcm2835_aux_update(s); +} + +static void bcm2835_aux_receive(void *opaque, const uint8_t *buf, int size) +{ + bcm2835_aux_put_fifo(opaque, *buf); +} + +static const MemoryRegionOps bcm2835_aux_ops = { + .read = bcm2835_aux_read, + .write = bcm2835_aux_write, + .endianness = DEVICE_NATIVE_ENDIAN, + .valid.min_access_size = 4, + .valid.max_access_size = 4, +}; + +static const VMStateDescription vmstate_bcm2835_aux = { + .name = TYPE_BCM2835_AUX, + .version_id = 1, + .minimum_version_id = 1, + .fields = (VMStateField[]) { + VMSTATE_UINT8_ARRAY(read_fifo, BCM2835AuxState, + BCM2835_AUX_RX_FIFO_LEN), + VMSTATE_UINT8(read_pos, BCM2835AuxState), + VMSTATE_UINT8(read_count, BCM2835AuxState), + VMSTATE_UINT8(ier, BCM2835AuxState), + VMSTATE_UINT8(iir, BCM2835AuxState), + VMSTATE_END_OF_LIST() + } +}; + +static void bcm2835_aux_init(Object *obj) +{ + SysBusDevice *sbd = SYS_BUS_DEVICE(obj); + BCM2835AuxState *s = BCM2835_AUX(obj); + + memory_region_init_io(&s->iomem, OBJECT(s), &bcm2835_aux_ops, s, + TYPE_BCM2835_AUX, 0x100); + sysbus_init_mmio(sbd, &s->iomem); + sysbus_init_irq(sbd, &s->irq); +} + +static void bcm2835_aux_realize(DeviceState *dev, Error **errp) +{ + BCM2835AuxState *s = BCM2835_AUX(dev); + + if (s->chr) { + qemu_chr_add_handlers(s->chr, bcm2835_aux_can_receive, + bcm2835_aux_receive, NULL, s); + } +} + +static Property bcm2835_aux_props[] = { + DEFINE_PROP_CHR("chardev", BCM2835AuxState, chr), + DEFINE_PROP_END_OF_LIST(), +}; + +static void bcm2835_aux_class_init(ObjectClass *oc, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(oc); + + dc->realize = bcm2835_aux_realize; + dc->vmsd = &vmstate_bcm2835_aux; + set_bit(DEVICE_CATEGORY_INPUT, dc->categories); + dc->props = bcm2835_aux_props; +} + +static const TypeInfo bcm2835_aux_info = { + .name = TYPE_BCM2835_AUX, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(BCM2835AuxState), + .instance_init = bcm2835_aux_init, + .class_init = bcm2835_aux_class_init, +}; + +static void bcm2835_aux_register_types(void) +{ + type_register_static(&bcm2835_aux_info); +} + +type_init(bcm2835_aux_register_types) diff --git a/include/hw/arm/bcm2835_peripherals.h b/include/hw/arm/bcm2835_peripherals.h index 5d888dc..889adf5 100644 --- a/include/hw/arm/bcm2835_peripherals.h +++ b/include/hw/arm/bcm2835_peripherals.h @@ -14,6 +14,7 @@ #include "qemu-common.h" #include "exec/address-spaces.h" #include "hw/sysbus.h" +#include "hw/char/bcm2835_aux.h" #include "hw/intc/bcm2835_ic.h" #include "hw/misc/bcm2835_property.h" #include "hw/misc/bcm2835_mbox.h" @@ -33,6 +34,7 @@ typedef struct BCM2835PeripheralState { qemu_irq irq, fiq; SysBusDevice *uart0; + BCM2835AuxState aux; BCM2835ICState ic; BCM2835PropertyState property; BCM2835MboxState mboxes; diff --git a/include/hw/char/bcm2835_aux.h b/include/hw/char/bcm2835_aux.h new file mode 100644 index 0000000..42f0ee7 --- /dev/null +++ b/include/hw/char/bcm2835_aux.h @@ -0,0 +1,33 @@ +/* + * Rasperry Pi 2 emulation and refactoring Copyright (c) 2015, Microsoft + * Written by Andrew Baumann + * + * This code is licensed under the GNU GPLv2 and later. + */ + +#ifndef BCM2835_AUX_H +#define BCM2835_AUX_H + +#include "hw/sysbus.h" +#include "sysemu/char.h" + +#define TYPE_BCM2835_AUX "bcm2835-aux" +#define BCM2835_AUX(obj) OBJECT_CHECK(BCM2835AuxState, (obj), TYPE_BCM2835_AUX) + +#define BCM2835_AUX_RX_FIFO_LEN 8 + +typedef struct { + /*< private >*/ + SysBusDevice parent_obj; + /*< public >*/ + + MemoryRegion iomem; + CharDriverState *chr; + qemu_irq irq; + + uint8_t read_fifo[BCM2835_AUX_RX_FIFO_LEN]; + uint8_t read_pos, read_count; + uint8_t ier, iir; +} BCM2835AuxState; + +#endif -- 2.7.4