From: Jared Rossi <[email protected]> Define common functionality for interacting with virtio-pci devices.
Signed-off-by: Jared Rossi <[email protected]> --- pc-bios/s390-ccw/Makefile | 2 +- pc-bios/s390-ccw/virtio-pci.c | 168 ++++++++++++++++++++++++++++++++++ pc-bios/s390-ccw/virtio-pci.h | 86 +++++++++++++++++ pc-bios/s390-ccw/virtio.h | 1 + 4 files changed, 256 insertions(+), 1 deletion(-) create mode 100644 pc-bios/s390-ccw/virtio-pci.c create mode 100644 pc-bios/s390-ccw/virtio-pci.h diff --git a/pc-bios/s390-ccw/Makefile b/pc-bios/s390-ccw/Makefile index a62fc9d766..3e5dfb64d5 100644 --- a/pc-bios/s390-ccw/Makefile +++ b/pc-bios/s390-ccw/Makefile @@ -35,7 +35,7 @@ QEMU_DGFLAGS = -MMD -MP -MT $@ -MF $(@D)/$(*F).d OBJECTS = start.o main.o bootmap.o jump2ipl.o sclp.o menu.o netmain.o \ virtio.o virtio-net.o virtio-scsi.o virtio-blkdev.o cio.o dasd-ipl.o \ - virtio-ccw.o clp.o pci.o + virtio-ccw.o clp.o pci.o virtio-pci.o SLOF_DIR := $(SRC_PATH)/../../roms/SLOF diff --git a/pc-bios/s390-ccw/virtio-pci.c b/pc-bios/s390-ccw/virtio-pci.c new file mode 100644 index 0000000000..70abac0256 --- /dev/null +++ b/pc-bios/s390-ccw/virtio-pci.c @@ -0,0 +1,168 @@ +/* + * Functionality for virtio-pci + * + * Copyright 2025 IBM Corp. + * Author(s): Jared Rossi <[email protected]> + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#include "clp.h" +#include "pci.h" +#include "helper.h" +#include "virtio.h" +#include "bswap.h" +#include "virtio-pci.h" +#include "s390-time.h" +#include <stdio.h> + +/* Variable offsets used for reads/writes to modern memory regions */ +VirtioPciCap c_cap; /* Common capabilities */ +VirtioPciCap d_cap; /* Device capabilities */ +VirtioPciCap n_cap; /* Notify capabilities */ +uint32_t notify_mult; +uint16_t q_notify_offset; + +static int virtio_pci_set_status(uint8_t status) +{ + int rc = vpci_write_byte(c_cap.off + VPCI_C_OFFSET_STATUS, c_cap.bar, status); + if (rc) { + puts("Failed to write virtio-pci status"); + return -EIO; + } + + return 0; +} + +static int virtio_pci_get_status(uint8_t *status) +{ + int rc = vpci_read_byte(c_cap.off + VPCI_C_OFFSET_STATUS, c_cap.bar, status); + if (rc) { + puts("Failed to read virtio-pci status"); + return -EIO; + } + + return 0; +} + +/* virtio spec v1.3 section 4.1.2.1 */ +void virtio_pci_id2type(VDev *vdev, uint16_t device_id) +{ + switch (device_id) { + case 0x1001: + vdev->dev_type = VIRTIO_ID_BLOCK; + break; + case 0x1000: /* Other valid but currently unsupported virtio device types */ + case 0x1004: + default: + vdev->dev_type = 0; + } +} + +int virtio_pci_reset(VDev *vdev) +{ + int rc; + uint8_t status = VPCI_S_RESET; + + rc = virtio_pci_set_status(status); + rc |= virtio_pci_get_status(&status); + + if (rc || status) { + puts("Failed to reset virtio-pci device"); + return 1; + } + + return 0; +} + +long virtio_pci_notify(int vq_id) +{ + uint32_t offset = n_cap.off + notify_mult * q_notify_offset; + return vpci_bswap16_write(offset, n_cap.bar, (uint16_t) vq_id); +} + +/* + * Wrappers to byte swap common data sizes then write + */ +int vpci_write_byte(uint64_t offset, uint8_t pcias, uint8_t data) +{ + return pci_write(virtio_get_device()->pci_fh, offset, pcias, (uint64_t) data, 1); +} + +int vpci_bswap16_write(uint64_t offset, uint8_t pcias, uint16_t data) +{ + uint64_t le_data = bswap16(data); + return pci_write(virtio_get_device()->pci_fh, offset, pcias, le_data, 2); +} + +int vpci_bswap32_write(uint64_t offset, uint8_t pcias, uint32_t data) +{ + uint64_t le_data = bswap32(data); + return pci_write(virtio_get_device()->pci_fh, offset, pcias, le_data, 4); +} + +int vpci_bswap64_write(uint64_t offset, uint8_t pcias, uint64_t data) +{ + uint64_t le_data = bswap64(data); + return pci_write(virtio_get_device()->pci_fh, offset, pcias, le_data, 8); +} + +/* + * Wrappers to read common data sizes then byte swap + */ +int vpci_read_byte(uint64_t offset, uint8_t pcias, uint8_t *buf) +{ + return pci_read(virtio_get_device()->pci_fh, offset, pcias, buf, 1); +} + +int vpci_read_bswap16(uint64_t offset, uint8_t pcias, uint16_t *buf) +{ + int rc = pci_read(virtio_get_device()->pci_fh, offset, pcias, buf, 2); + *buf = bswap16(*buf); + return rc; +} + +int vpci_read_bswap32(uint64_t offset, uint8_t pcias, uint32_t *buf) +{ + int rc = pci_read(virtio_get_device()->pci_fh, offset, pcias, buf, 4); + *buf = bswap32(*buf); + return rc; +} + +int vpci_read_bswap64(uint64_t offset, uint8_t pcias, uint64_t *buf) +{ + int rc = pci_read(virtio_get_device()->pci_fh, offset, pcias, buf, 8); + *buf = bswap64(*buf); + return rc; +} + +/* + * Read to an arbitrary length buffer without byte swapping + */ +int vpci_read_flex(uint64_t offset, uint8_t pcias, void *buf, int len) +{ + uint8_t readlen; + int rc; + int remaining = len; + + /* Read bytes in powers of 2, up to a maximum of 8 bytes per read */ + while (remaining) { + for (int i = 3; i >= 0; i--) { + readlen = 1 << i; + if (remaining >= readlen) { + break; + } + } + + rc = pci_read(virtio_get_device()->pci_fh, offset, pcias, buf, readlen); + if (rc) { + return -1; + } + + remaining -= readlen; + buf += readlen; + offset += readlen; + } + + return 0; +} diff --git a/pc-bios/s390-ccw/virtio-pci.h b/pc-bios/s390-ccw/virtio-pci.h new file mode 100644 index 0000000000..96c17ac3c7 --- /dev/null +++ b/pc-bios/s390-ccw/virtio-pci.h @@ -0,0 +1,86 @@ +/* + * Definitions for virtio-pci + * + * Copyright 2025 IBM Corp. + * Author(s): Jared Rossi <[email protected]> + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#ifndef VIRTIO_PCI_H +#define VIRTIO_PCI_H + +/* Common configuration */ +#define VPCI_CAP_COMMON_CFG 1 +/* Notifications */ +#define VPCI_CAP_NOTIFY_CFG 2 +/* ISR access */ +#define VPCI_CAP_ISR_CFG 3 +/* Device specific configuration */ +#define VPCI_CAP_DEVICE_CFG 4 +/* PCI configuration access */ +#define VPCI_CAP_PCI_CFG 5 +/* Additional shared memory capability */ +#define VPCI_CAP_SHARED_MEMORY_CFG 8 +/* PCI vendor data configuration */ +#define VPCI_CAP_VENDOR_CFG 9 + +/* Offsets within capability header */ +#define VPCI_CAP_VNDR 0 +#define VPCI_CAP_NEXT 1 +#define VPCI_CAP_LEN 2 +#define VPCI_CAP_CFG_TYPE 3 +#define VPCI_CAP_BAR 4 +#define VPCI_CAP_OFFSET 8 +#define VPCI_CAP_LENGTH 12 + +#define VPCI_N_CAP_MULT 16 /* Notify multiplier, VPCI_CAP_NOTIFY_CFG only */ + +/* Common Area Offsets for virtio-pci queue */ +#define VPCI_C_OFFSET_DFSELECT 0 +#define VPCI_C_OFFSET_DF 4 +#define VPCI_C_OFFSET_GFSELECT 8 +#define VPCI_C_OFFSET_GF 12 +#define VPCI_C_COMMON_NUMQ 18 +#define VPCI_C_OFFSET_STATUS 20 +#define VPCI_C_OFFSET_Q_SELECT 22 +#define VPCI_C_OFFSET_Q_SIZE 24 +#define VPCI_C_OFFSET_Q_ENABLE 28 +#define VPCI_C_OFFSET_Q_NOFF 30 +#define VPCI_C_OFFSET_Q_DESCLO 32 +#define VPCI_C_OFFSET_Q_DESCHI 36 +#define VPCI_C_OFFSET_Q_AVAILLO 40 +#define VPCI_C_OFFSET_Q_AVAILHI 44 +#define VPCI_C_OFFSET_Q_USEDLO 48 +#define VPCI_C_OFFSET_Q_USEDHI 52 + +#define VPCI_S_RESET 0 +#define VPCI_S_ACKNOWLEDGE 1 +#define VPCI_S_DRIVER 2 +#define VPCI_S_DRIVER_OK 4 +#define VPCI_S_FEATURES_OK 8 + +#define VIRTIO_F_VERSION_1 (1 << (32 - 32)) /* Feature bit 32 */ + +struct VirtioPciCap { + uint8_t bar; /* Which PCIAS it's in */ + uint32_t off; /* Offset within bar */ +}; +typedef struct VirtioPciCap VirtioPciCap; + +void virtio_pci_id2type(VDev *vdev, uint16_t device_id); +int virtio_pci_reset(VDev *vdev); +long virtio_pci_notify(int vq_id); + +int vpci_read_flex(uint64_t offset, uint8_t pcias, void *buf, int len); +int vpci_read_bswap64(uint64_t offset, uint8_t pcias, uint64_t *buf); +int vpci_read_bswap32(uint64_t offset, uint8_t pcias, uint32_t *buf); +int vpci_read_bswap16(uint64_t offset, uint8_t pcias, uint16_t *buf); +int vpci_read_byte(uint64_t offset, uint8_t pcias, uint8_t *buf); + +int vpci_bswap64_write(uint64_t offset, uint8_t pcias, uint64_t data); +int vpci_bswap32_write(uint64_t offset, uint8_t pcias, uint32_t data); +int vpci_bswap16_write(uint64_t offset, uint8_t pcias, uint16_t data); +int vpci_write_byte(uint64_t offset, uint8_t pcias, uint8_t data); + +#endif diff --git a/pc-bios/s390-ccw/virtio.h b/pc-bios/s390-ccw/virtio.h index 0fdee8468c..0c34d59be2 100644 --- a/pc-bios/s390-ccw/virtio.h +++ b/pc-bios/s390-ccw/virtio.h @@ -255,6 +255,7 @@ struct VDev { uint8_t scsi_dev_heads; bool scsi_device_selected; ScsiDevice selected_scsi_device; + uint32_t pci_fh; uint32_t max_transfer; uint32_t guest_features[2]; }; -- 2.52.0
