linux-stable/include/acpi/pcc.h
Adam Young 7f9e19f207 mailbox: pcc: Check before sending MCTP PCC response ACK
Type 4 PCC channels have an option to send back a response
to the platform when they are done processing the request.
The flag to indicate whether or not to respond is inside
the message body, and thus is not available to the pcc
mailbox.

If the flag is not set, still set command completion
bit after processing message.

In order to read the flag, this patch maps the shared
buffer to virtual memory. To avoid duplication of mapping
the shared buffer is then made available to be used by
the driver that uses the mailbox.

Signed-off-by: Adam Young <admiyo@os.amperecomputing.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>
2024-11-24 13:20:40 -06:00

56 lines
1.4 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* PCC (Platform Communications Channel) methods
*/
#ifndef _PCC_H
#define _PCC_H
#include <linux/mailbox_controller.h>
#include <linux/mailbox_client.h>
struct pcc_mbox_chan {
struct mbox_chan *mchan;
u64 shmem_base_addr;
void __iomem *shmem;
u64 shmem_size;
u32 latency;
u32 max_access_rate;
u16 min_turnaround_time;
};
/* Generic Communications Channel Shared Memory Region */
#define PCC_SIGNATURE 0x50434300
/* Generic Communications Channel Command Field */
#define PCC_CMD_GENERATE_DB_INTR BIT(15)
/* Generic Communications Channel Status Field */
#define PCC_STATUS_CMD_COMPLETE BIT(0)
#define PCC_STATUS_SCI_DOORBELL BIT(1)
#define PCC_STATUS_ERROR BIT(2)
#define PCC_STATUS_PLATFORM_NOTIFY BIT(3)
/* Initiator Responder Communications Channel Flags */
#define PCC_CMD_COMPLETION_NOTIFY BIT(0)
#define MAX_PCC_SUBSPACES 256
#define PCC_ACK_FLAG_MASK 0x1
#ifdef CONFIG_PCC
extern struct pcc_mbox_chan *
pcc_mbox_request_channel(struct mbox_client *cl, int subspace_id);
extern void pcc_mbox_free_channel(struct pcc_mbox_chan *chan);
extern int pcc_mbox_ioremap(struct mbox_chan *chan);
#else
static inline struct pcc_mbox_chan *
pcc_mbox_request_channel(struct mbox_client *cl, int subspace_id)
{
return ERR_PTR(-ENODEV);
}
static inline void pcc_mbox_free_channel(struct pcc_mbox_chan *chan) { }
static inline int pcc_mbox_ioremap(struct mbox_chan *chan)
{
return 0;
};
#endif
#endif /* _PCC_H */