[SLOF] [PATCH v1 07/27] virtio: add virtio 1.0 capability parsing
Nikunj A Dadhania
nikunj at linux.vnet.ibm.com
Thu Jan 14 21:45:23 AEDT 2016
Alexey Kardashevskiy <aik at ozlabs.ru> writes:
> On 01/13/2016 10:16 PM, Nikunj A Dadhania wrote:
>> Signed-off-by: Nikunj A Dadhania <nikunj at linux.vnet.ibm.com>
>> ---
>> lib/libvirtio/virtio.c | 135 +++++++++++++++++++++++++++++++++++++++++++++++++
>> lib/libvirtio/virtio.h | 3 +-
>> 2 files changed, 137 insertions(+), 1 deletion(-)
>>
>> diff --git a/lib/libvirtio/virtio.c b/lib/libvirtio/virtio.c
>> index 7e0d6a3..bcf050b 100644
>> --- a/lib/libvirtio/virtio.c
>> +++ b/lib/libvirtio/virtio.c
>> @@ -14,6 +14,7 @@
>> #include <stdbool.h>
>> #include <stdlib.h>
>> #include <string.h>
>> +#include <stddef.h>
>> #include <cpu.h>
>> #include <cache.h>
>> #include <byteorder.h>
>> @@ -31,6 +32,140 @@
>> #define VIRTIOHDR_ISR_STATUS 19
>> #define VIRTIOHDR_DEVICE_CONFIG 20
>>
>> +/* PCI defines */
>> +#define PCI_BASE_ADDR_SPACE_IO 0x01
>> +#define PCI_BASE_ADDR_SPACE_MEM 0x00
>> +#define PCI_BASE_ADDR_MEM_MASK (~0x0fUL)
>> +#define PCI_BASE_ADDR_IO_MASK (~0x03UL)
>> +
>> +#define PCI_BASE_ADDR_REG_0 0x10
>> +#define PCI_CONFIG_CAP_REG 0x34
>> +
>> +#define PCI_CAP_ID_VNDR 0x9
>> +
>> +#define VIRTIO_PCI_CAP_COMMON 1
>> +#define VIRTIO_PCI_CAP_NOTIFY 2
>> +#define VIRTIO_PCI_CAP_ISR 3
>> +#define VIRTIO_PCI_CAP_DEVICE 4
>> +#define VIRTIO_PCI_CAP_PCI 5
>> +
>> +#define VIRTIO_CAP_VNDR 0
>> +#define VIRTIO_CAP_NEXT 1
>> +#define VIRTIO_CAP_LEN 2
>> +#define VIRTIO_CAP_CFG_TYPE 3
>> +#define VIRTIO_CAP_BAR 4
>> +#define VIRTIO_CAP_OFFSET 8
>> +#define VIRTIO_CAP_LENGTH 12
>
>
> VIRTIO_CAP_LEN and VIRTIO_CAP_LENGTH - how are they different? I could not
> figure out from the code as they are not used at all.
VIRTIO_CAP_LEN - Capability length
VIRTIO_CAP_LENGTH - Length of the virtio structure pointed by
"addr[bar]+ offset"
>From the virtio 1.0 spec
struct virtio_pci_cap {
u8 cap_vndr; /* Generic PCI field: PCI_CAP_ID_VNDR */
u8 cap_next; /* Generic PCI field: next ptr. */
u8 cap_len; /* Generic PCI field: capability length */
u8 cfg_type; /* Identifies the structure. */
u8 bar; /* Where to find it. */
u8 padding[3]; /* Pad to full dword. */
le32 offset; /* Offset within the bar. */
le32 length; /* Length of the structure, in bytes. */
};
>
>
>> +
>> +#define le64 uint64_t
>> +#define le32 uint32_t
>> +#define le16 uint16_t
>
>
> I'd use:
>
> typedef __u16 __bitwise __le16;
> typedef __u16 __bitwise __be16;
> typedef __u32 __bitwise __le32;
> typedef __u32 __bitwise __be32;
> typedef __u64 __bitwise __le64;
> typedef __u64 __bitwise __be64;
>
> as include/uapi/linux/types.h does in the kernel.
Sure. I can take that.
>
>> +
>> +struct virtio_dev_common {
>> + le32 dev_features_sel;
>> + le32 dev_features;
>> + le32 drv_features_sel;
>> + le32 drv_features;
>> + le16 msix_config;
>> + le16 num_queues;
>> + uint8_t dev_status;
>> + uint8_t cfg_generation;
>> +
>> + le16 q_select;
>> + le16 q_size;
>> + le16 q_msix_vec;
>> + le16 q_enable;
>> + le16 q_notify_off;
>> + le64 q_desc;
>> + le64 q_avail;
>> + le64 q_used;
>> +} __attribute__ ((packed));
>> +
>> +static void virtio_process_cap(struct virtio_device *dev, uint8_t cap_ptr)
>> +{
>> + struct virtio_cap *cap;
>> + uint8_t cfg_type, bar;
>> + uint32_t offset;
>> + uint64_t addr = 0;
>> +
>> + cfg_type = SLOF_pci_config_read8(cap_ptr + VIRTIO_CAP_CFG_TYPE);
>> + bar = SLOF_pci_config_read8(cap_ptr + VIRTIO_CAP_BAR);
>> + offset = SLOF_pci_config_read32(cap_ptr + VIRTIO_CAP_OFFSET);
>> +
>> + switch(cfg_type) {
>> + case VIRTIO_PCI_CAP_COMMON:
>> + cap = &dev->common;
>> + break;
>> + case VIRTIO_PCI_CAP_NOTIFY:
>> + cap = &dev->notify;
>> + dev->notify_off_mul = SLOF_pci_config_read32(cap_ptr + sizeof(struct virtio_cap));
>> + break;
>> + case VIRTIO_PCI_CAP_ISR:
>> + cap = &dev->isr;
>> + break;
>> + case VIRTIO_PCI_CAP_DEVICE:
>> + cap = &dev->device;
>> + break;
>> + default:
>> + cap = NULL;
>> + }
>> +
>> + if (cap && cfg_type) {
>> + cap->bar = bar;
>> + addr = SLOF_pci_config_read32(PCI_BASE_ADDR_REG_0 + 4 * cap->bar);
>> + if (addr & PCI_BASE_ADDR_SPACE_IO) {
>> + cap->is_io = 1;
>> + addr = addr & PCI_BASE_ADDR_IO_MASK;
>> + } else if (addr & 4) {
>> + addr = SLOF_pci_config_read32(PCI_BASE_ADDR_REG_0 + 4 * cap->bar) |
>> + (SLOF_pci_config_read32(PCI_BASE_ADDR_REG_0 + 4 * (cap->bar + 1)) << 32);
>> + addr = (uint64_t)SLOF_translate_my_address((void *)addr);
>> + addr = addr & PCI_BASE_ADDR_MEM_MASK;
>> + }
>> + else {
>> + cap->is_io = 0;
>> + addr = addr & PCI_BASE_ADDR_MEM_MASK;
>> + }
>> + cap->addr = (void *)addr + offset;
>> + cap->cap_id = cfg_type;
>> + }
>> + return;
>> +}
>> +/**
>> + * Setup virtio device details, gets called from SLOF routines
>> + * Determines legacy or modern device.
>> + */
>> +void virtio_setup_device(struct virtio_device *dev)
>
>
> s/virtio_setup_device/virtio_parse_capabilities/ ? This function does not
> set up anything...w
Sure.
>
>
>> +{
>> + uint8_t cap_ptr, cap_vndr;
>> + uint64_t addr = 0;
>> +
>> + cap_ptr = SLOF_pci_config_read8(PCI_CONFIG_CAP_REG);
>> + while (cap_ptr != 0)
>> + {
>> + cap_vndr = SLOF_pci_config_read8(cap_ptr + VIRTIO_CAP_VNDR);
>> + if (cap_vndr == PCI_CAP_ID_VNDR)
>> + virtio_process_cap(dev, cap_ptr);
>> + cap_ptr = SLOF_pci_config_read8(cap_ptr+VIRTIO_CAP_NEXT);
>> + }
>> + if (dev->common.cap_id && dev->notify.cap_id && dev->isr.cap_id && dev->device.cap_id)
>> + dev->is_modern = 1;
>> + else {
>> + dev->is_modern = 0;
>> + dev->legacy.cap_id = 0;
>> + dev->legacy.bar = 0;
>> + addr = SLOF_pci_config_read32(PCI_BASE_ADDR_REG_0);
>> + if (addr & PCI_BASE_ADDR_SPACE_IO) {
>> + dev->legacy.is_io = 1;
>> + addr = addr & PCI_BASE_ADDR_IO_MASK;
>> + } else {
>> + dev->legacy.is_io = 0;
>> + addr = addr & PCI_BASE_ADDR_MEM_MASK;
>> + }
>> + dev->legacy.addr = (void *)addr;
>> + }
>> + return;
>> +}
>>
>> /**
>> * Calculate ring size according to queue size number
>> diff --git a/lib/libvirtio/virtio.h b/lib/libvirtio/virtio.h
>> index 56e044b..eee3144 100644
>> --- a/lib/libvirtio/virtio.h
>> +++ b/lib/libvirtio/virtio.h
>> @@ -74,7 +74,7 @@ struct vring_used {
>>
>> /* Structure shared with SLOF and is 16bytes */
>> struct virtio_cap {
>> - uint64_t addr;
>> + void *addr;
>> uint8_t bar;
>> uint8_t is_io;
>> uint8_t cap_id;
>> @@ -116,6 +116,7 @@ extern void virtio_fill_desc(struct vring_desc *desc,
>> uint16_t flags, uint16_t next);
>> extern int virtio_queue_init_vq(struct virtio_device *dev, struct vqs *vq, unsigned int id);
>>
>> +extern void virtio_setup_device(struct virtio_device *dev);
>> extern void virtio_reset_device(struct virtio_device *dev);
>> extern void virtio_queue_notify(struct virtio_device *dev, int queue);
>> extern void virtio_set_status(struct virtio_device *dev, int status);
>>
>
>
> The whole patch seems to belong to 18/27.
why ?
Regards
Nikunj
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