Commit 39a08a4f authored by Haren Myneni's avatar Haren Myneni Committed by Madhavan Srinivasan
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powerpc/pseries: Enable hvpipe with ibm,set-system-parameter RTAS 



The partition uses “Hypervisor Pipe OS Enablement Notification”
system parameter token (value = 64) to enable / disable hvpipe in
the hypervisor. Once hvpipe is enabled, the hypervisor notifies
OS if the payload is pending for that partition from any source.
This system parameter token takes 1 byte length of data with
1 = Enable and 0 = Disable.

Enable hvpipe in the hypervisor with ibm,set-system-parameter
RTAS after registering hvpipe event source interrupt.

Signed-off-by: default avatarHaren Myneni <haren@linux.ibm.com>
Tested-by: default avatarShashank MS <shashank.gowda@in.ibm.com>
Reviewed-by: default avatarMahesh Salgaonkar <mahesh@linux.ibm.com>
Reviewed-by: default avatarTyrel Datwyler <tyreld@linux.ibm.com>
Signed-off-by: default avatarMadhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250909084402.1488456-9-haren@linux.ibm.com
parent b48b6cc8

arch/powerpc/include/asm/papr-sysparm.h

+1 −0
Original line number Diff line number Diff line
@@ -21,6 +21,7 @@ typedef struct { 
#define PAPR_SYSPARM_COOP_MEM_OVERCOMMIT_ATTRS     mk_papr_sysparm(44)

#define PAPR_SYSPARM_TLB_BLOCK_INVALIDATE_ATTRS    mk_papr_sysparm(50)

#define PAPR_SYSPARM_LPAR_NAME                     mk_papr_sysparm(55)

#define PAPR_SYSPARM_HVPIPE_ENABLE                 mk_papr_sysparm(64)



/**

 * struct papr_sysparm_buf - RTAS work area layout for system parameter functions.

arch/powerpc/platforms/pseries/papr-hvpipe.c

+32 −2
Original line number Diff line number Diff line
@@ -15,6 +15,7 @@ 
#include <asm/machdep.h>

#include <asm/rtas.h>

#include <asm/rtas-work-area.h>

#include <asm/papr-sysparm.h>

#include <uapi/asm/papr-hvpipe.h>

#include "pseries.h"

#include "papr-hvpipe.h"
@@ -648,6 +649,32 @@ static irqreturn_t hvpipe_event_interrupt(int irq, void *dev_id) 
	return IRQ_HANDLED;

}



/*

 * Enable hvpipe by system parameter set with parameter

 * token = 64 and with 1 byte buffer data:

 * 0 = hvpipe not in use/disable

 * 1 = hvpipe in use/enable

 */

static int set_hvpipe_sys_param(u8 val)

{

	struct papr_sysparm_buf *buf;

	int ret;



	buf = papr_sysparm_buf_alloc();

	if (!buf)

		return -ENOMEM;



	buf->len = cpu_to_be16(1);

	buf->val[0] = val;

	ret = papr_sysparm_set(PAPR_SYSPARM_HVPIPE_ENABLE, buf);

	if (ret)

		pr_err("Can not enable hvpipe %d\n", ret);



	papr_sysparm_buf_free(buf);



	return ret;

}



static int __init enable_hvpipe_IRQ(void)

{

	struct device_node *np;
@@ -705,8 +732,11 @@ static int __init papr_hvpipe_init(void) 
	}



	ret = enable_hvpipe_IRQ();

	if (!ret) {

		ret = set_hvpipe_sys_param(1);

		if (!ret)

			ret = misc_register(&papr_hvpipe_dev);

	}



	if (!ret) {

		pr_info("hvpipe feature is enabled\n");