mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-10-30 08:02:30 +00:00
Code Issues Releases Wiki Activity

drm/vmwgfx: Use the backdoor port if the HB port is not available

Browse source 
The HB port may not be available for various reasons. Either it has been
disabled by a config option or by the hypervisor for other reasons.
In that case, make sure we have a backup plan and use the backdoor port
instead with a performance penalty.

Cc: stable@vger.kernel.org
Fixes: 89da76fde6 ("drm/vmwgfx: Add VMWare host messaging capability")
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Deepak Rawat <drawat@vmware.com>
This commit is contained in:
Thomas Hellstrom 2019-05-29 08:15:19 +02:00
parent 5ed7f4b5ec
commit cc0ba0d862
1 changed files with 117 additions and 29 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

146
drivers/gpu/drm/vmwgfx/vmwgfx_msg.c
View file

@ -136,6 +136,114 @@ static int vmw_close_channel(struct rpc_channel *channel)
return 0;
}
/**
* vmw_port_hb_out - Send the message payload either through the
* high-bandwidth port if available, or through the backdoor otherwise.
* @channel: The rpc channel.
* @msg: NULL-terminated message.
* @hb: Whether the high-bandwidth port is available.
*
* Return: The port status.
*/
static unsigned long vmw_port_hb_out(struct rpc_channel *channel,
const char *msg, bool hb)
{
unsigned long si, di, eax, ebx, ecx, edx;
unsigned long msg_len = strlen(msg);
if (hb) {
unsigned long bp = channel->cookie_high;
si = (uintptr_t) msg;
di = channel->cookie_low;
VMW_PORT_HB_OUT(
(MESSAGE_STATUS_SUCCESS << 16) | VMW_PORT_CMD_HB_MSG,
msg_len, si, di,
VMW_HYPERVISOR_HB_PORT | (channel->channel_id << 16),
VMW_HYPERVISOR_MAGIC, bp,
eax, ebx, ecx, edx, si, di);
return ebx;
}
/* HB port not available. Send the message 4 bytes at a time. */
ecx = MESSAGE_STATUS_SUCCESS << 16;
while (msg_len && (HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS)) {
unsigned int bytes = min_t(size_t, msg_len, 4);
unsigned long word = 0;
memcpy(&word, msg, bytes);
msg_len -= bytes;
msg += bytes;
si = channel->cookie_high;
di = channel->cookie_low;
VMW_PORT(VMW_PORT_CMD_MSG | (MSG_TYPE_SENDPAYLOAD << 16),
word, si, di,
VMW_HYPERVISOR_PORT | (channel->channel_id << 16),
VMW_HYPERVISOR_MAGIC,
eax, ebx, ecx, edx, si, di);
}
return ecx;
}
/**
* vmw_port_hb_in - Receive the message payload either through the
* high-bandwidth port if available, or through the backdoor otherwise.
* @channel: The rpc channel.
* @reply: Pointer to buffer holding reply.
* @reply_len: Length of the reply.
* @hb: Whether the high-bandwidth port is available.
*
* Return: The port status.
*/
static unsigned long vmw_port_hb_in(struct rpc_channel *channel, char *reply,
unsigned long reply_len, bool hb)
{
unsigned long si, di, eax, ebx, ecx, edx;
if (hb) {
unsigned long bp = channel->cookie_low;
si = channel->cookie_high;
di = (uintptr_t) reply;
VMW_PORT_HB_IN(
(MESSAGE_STATUS_SUCCESS << 16) | VMW_PORT_CMD_HB_MSG,
reply_len, si, di,
VMW_HYPERVISOR_HB_PORT | (channel->channel_id << 16),
VMW_HYPERVISOR_MAGIC, bp,
eax, ebx, ecx, edx, si, di);
return ebx;
}
/* HB port not available. Retrieve the message 4 bytes at a time. */
ecx = MESSAGE_STATUS_SUCCESS << 16;
while (reply_len) {
unsigned int bytes = min_t(unsigned long, reply_len, 4);
si = channel->cookie_high;
di = channel->cookie_low;
VMW_PORT(VMW_PORT_CMD_MSG | (MSG_TYPE_RECVPAYLOAD << 16),
MESSAGE_STATUS_SUCCESS, si, di,
VMW_HYPERVISOR_PORT | (channel->channel_id << 16),
VMW_HYPERVISOR_MAGIC,
eax, ebx, ecx, edx, si, di);
if ((HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS) == 0)
break;
memcpy(reply, &ebx, bytes);
reply_len -= bytes;
reply += bytes;
}
return ecx;
}
/**
@ -148,11 +256,10 @@ static int vmw_close_channel(struct rpc_channel *channel)
*/
static int vmw_send_msg(struct rpc_channel *channel, const char *msg)
{
unsigned long eax, ebx, ecx, edx, si, di, bp;
unsigned long eax, ebx, ecx, edx, si, di;
size_t msg_len = strlen(msg);
int retries = 0;
while (retries < RETRIES) {
retries++;
@ -166,23 +273,14 @@ static int vmw_send_msg(struct rpc_channel *channel, const char *msg)
VMW_HYPERVISOR_MAGIC,
eax, ebx, ecx, edx, si, di);
if ((HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS) == 0 ||
(HIGH_WORD(ecx) & MESSAGE_STATUS_HB) == 0) {
/* Expected success + high-bandwidth. Give up. */
if ((HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS) == 0) {
/* Expected success. Give up. */
return -EINVAL;
}
/* Send msg */
si = (uintptr_t) msg;
di = channel->cookie_low;
bp = channel->cookie_high;
VMW_PORT_HB_OUT(
(MESSAGE_STATUS_SUCCESS << 16) | VMW_PORT_CMD_HB_MSG,
msg_len, si, di,
VMW_HYPERVISOR_HB_PORT | (channel->channel_id << 16),
VMW_HYPERVISOR_MAGIC, bp,
eax, ebx, ecx, edx, si, di);
ebx = vmw_port_hb_out(channel, msg,
!!(HIGH_WORD(ecx) & MESSAGE_STATUS_HB));
if ((HIGH_WORD(ebx) & MESSAGE_STATUS_SUCCESS) != 0) {
return 0;
@ -211,7 +309,7 @@ STACK_FRAME_NON_STANDARD(vmw_send_msg);
static int vmw_recv_msg(struct rpc_channel *channel, void **msg,
size_t *msg_len)
{
unsigned long eax, ebx, ecx, edx, si, di, bp;
unsigned long eax, ebx, ecx, edx, si, di;
char *reply;
size_t reply_len;
int retries = 0;
@ -233,8 +331,7 @@ static int vmw_recv_msg(struct rpc_channel *channel, void **msg,
VMW_HYPERVISOR_MAGIC,
eax, ebx, ecx, edx, si, di);
if ((HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS) == 0 ||
(HIGH_WORD(ecx) & MESSAGE_STATUS_HB) == 0) {
if ((HIGH_WORD(ecx) & MESSAGE_STATUS_SUCCESS) == 0) {
DRM_ERROR("Failed to get reply size for host message.\n");
return -EINVAL;
}
@ -252,17 +349,8 @@ static int vmw_recv_msg(struct rpc_channel *channel, void **msg,
/* Receive buffer */
si = channel->cookie_high;
di = (uintptr_t) reply;
bp = channel->cookie_low;
VMW_PORT_HB_IN(
(MESSAGE_STATUS_SUCCESS << 16) | VMW_PORT_CMD_HB_MSG,
reply_len, si, di,
VMW_HYPERVISOR_HB_PORT | (channel->channel_id << 16),
VMW_HYPERVISOR_MAGIC, bp,
eax, ebx, ecx, edx, si, di);
ebx = vmw_port_hb_in(channel, reply, reply_len,
!!(HIGH_WORD(ecx) & MESSAGE_STATUS_HB));
if ((HIGH_WORD(ebx) & MESSAGE_STATUS_SUCCESS) == 0) {
kfree(reply);