qemu/hw/spapr_vio.h
Ben Herrenschmidt 08942ac179 Add a PAPR TCE-bypass mechanism for the pSeries machine
Usually, PAPR virtual IO devices use a virtual IOMMU mechanism, TCEs,
to mediate all DMA transfers.  While this is necessary for some sorts of
operation, it can be complex to program and slow for others.

This patch implements a mechanism for bypassing TCE translation, treating
"IO" addresses as plain (guest) physical memory addresses.  This has two
main uses:
 * Simple, but 64-bit aware programs like firmwares can use the VIO devices
without the complexity of TCE setup.
 * The guest OS can optionally use the TCE bypass to improve performance in
suitable situations.

The mechanism used is a per-device flag which disables TCE translation.
The flag is toggled with some (hypervisor-implemented) RTAS methods.

Signed-off-by: Ben Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-04-01 18:34:57 +02:00

113 lines
3.8 KiB
C

#ifndef _HW_SPAPR_VIO_H
#define _HW_SPAPR_VIO_H
/*
* QEMU sPAPR VIO bus definitions
*
* Copyright (c) 2010 David Gibson, IBM Corporation <david@gibson.dropbear.id.au>
* Based on the s390 virtio bus definitions:
* Copyright (c) 2009 Alexander Graf <agraf@suse.de>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#define SPAPR_VIO_TCE_PAGE_SHIFT 12
#define SPAPR_VIO_TCE_PAGE_SIZE (1ULL << SPAPR_VIO_TCE_PAGE_SHIFT)
#define SPAPR_VIO_TCE_PAGE_MASK (SPAPR_VIO_TCE_PAGE_SIZE - 1)
enum VIOsPAPR_TCEAccess {
SPAPR_TCE_FAULT = 0,
SPAPR_TCE_RO = 1,
SPAPR_TCE_WO = 2,
SPAPR_TCE_RW = 3,
};
struct VIOsPAPRDevice;
typedef struct VIOsPAPR_RTCE {
uint64_t tce;
} VIOsPAPR_RTCE;
typedef struct VIOsPAPR_CRQ {
uint64_t qladdr;
uint32_t qsize;
uint32_t qnext;
int(*SendFunc)(struct VIOsPAPRDevice *vdev, uint8_t *crq);
} VIOsPAPR_CRQ;
typedef struct VIOsPAPRDevice {
DeviceState qdev;
uint32_t reg;
uint32_t flags;
#define VIO_PAPR_FLAG_DMA_BYPASS 0x1
qemu_irq qirq;
uint32_t vio_irq_num;
target_ulong signal_state;
uint32_t rtce_window_size;
VIOsPAPR_RTCE *rtce_table;
VIOsPAPR_CRQ crq;
} VIOsPAPRDevice;
typedef struct VIOsPAPRBus {
BusState bus;
} VIOsPAPRBus;
typedef struct {
DeviceInfo qdev;
const char *dt_name, *dt_type, *dt_compatible;
target_ulong signal_mask;
int (*init)(VIOsPAPRDevice *dev);
void (*hcalls)(VIOsPAPRBus *bus);
int (*devnode)(VIOsPAPRDevice *dev, void *fdt, int node_off);
} VIOsPAPRDeviceInfo;
extern VIOsPAPRBus *spapr_vio_bus_init(void);
extern VIOsPAPRDevice *spapr_vio_find_by_reg(VIOsPAPRBus *bus, uint32_t reg);
extern void spapr_vio_bus_register_withprop(VIOsPAPRDeviceInfo *info);
extern int spapr_populate_vdevice(VIOsPAPRBus *bus, void *fdt);
extern int spapr_vio_signal(VIOsPAPRDevice *dev, target_ulong mode);
int spapr_vio_check_tces(VIOsPAPRDevice *dev, target_ulong ioba,
target_ulong len,
enum VIOsPAPR_TCEAccess access);
int spapr_tce_dma_read(VIOsPAPRDevice *dev, uint64_t taddr,
void *buf, uint32_t size);
int spapr_tce_dma_write(VIOsPAPRDevice *dev, uint64_t taddr,
const void *buf, uint32_t size);
int spapr_tce_dma_zero(VIOsPAPRDevice *dev, uint64_t taddr, uint32_t size);
void stb_tce(VIOsPAPRDevice *dev, uint64_t taddr, uint8_t val);
void sth_tce(VIOsPAPRDevice *dev, uint64_t taddr, uint16_t val);
void stw_tce(VIOsPAPRDevice *dev, uint64_t taddr, uint32_t val);
void stq_tce(VIOsPAPRDevice *dev, uint64_t taddr, uint64_t val);
uint64_t ldq_tce(VIOsPAPRDevice *dev, uint64_t taddr);
int spapr_vio_send_crq(VIOsPAPRDevice *dev, uint8_t *crq);
void vty_putchars(VIOsPAPRDevice *sdev, uint8_t *buf, int len);
void spapr_vty_create(VIOsPAPRBus *bus,
uint32_t reg, CharDriverState *chardev,
qemu_irq qirq, uint32_t vio_irq_num);
void spapr_vlan_create(VIOsPAPRBus *bus, uint32_t reg, NICInfo *nd,
qemu_irq qirq, uint32_t vio_irq_num);
void spapr_vscsi_create(VIOsPAPRBus *bus, uint32_t reg,
qemu_irq qirq, uint32_t vio_irq_num);
int spapr_tce_set_bypass(uint32_t unit, uint32_t enable);
void spapr_vio_quiesce(void);
#endif /* _HW_SPAPR_VIO_H */