Subject: Re: [PATCH v5 10/18] cxl: New hcalls to support cxl adapters

From: Manoj Kumar <[email-masked]>
Date: Tue, 23 Feb 2016 13:23:54 -0600

Fred: Thanks for correcting those spellings.

Reviewed-by: Manoj Kumar <[email-masked]>

---
Manoj Kumar

On 2/23/2016 10:21 AM, Frederic Barrat wrote:
> From: Christophe Lombard <[email-masked]>
>
> The hypervisor calls provide an interface with a coherent platform
> facility and function. It matches version 0.16 of the 'PAPR changes'
> document.
>
> The following hcalls are supported:
> H_ATTACH_CA_PROCESS    Attach a process element to a coherent platform
>                         function.
> H_DETACH_CA_PROCESS    Detach a process element from a coherent
>                         platform function.
> H_CONTROL_CA_FUNCTION  Allow the partition to manipulate or query
>                         certain coherent platform function behaviors.
> H_COLLECT_CA_INT_INFO  Collect interrupt info about a coherent.
>                         platform function after an interrupt occurred
> H_CONTROL_CA_FAULTS    Control the operation of a coherent platform
>                         function after a fault occurs.
> H_DOWNLOAD_CA_FACILITY Support for downloading a base adapter image to
>                         the coherent platform facility, and for
>                         validating the entire image after the download.
> H_CONTROL_CA_FACILITY  Allow the partition to manipulate or query
>                         certain coherent platform facility behaviors.
>
> Co-authored-by: Frederic Barrat <[email-masked]>
> Signed-off-by: Frederic Barrat <[email-masked]>
> Signed-off-by: Christophe Lombard <[email-masked]>
> ---
>   drivers/misc/cxl/cxl.h    |  23 +-
>   drivers/misc/cxl/hcalls.c | 639 ++++++++++++++++++++++++++++++++++++++++++++++
>   drivers/misc/cxl/hcalls.h | 203 +++++++++++++++
>   drivers/misc/cxl/main.c   |  26 ++
>   drivers/misc/cxl/native.c |   1 +
>   5 files changed, 890 insertions(+), 2 deletions(-)
>   create mode 100644 drivers/misc/cxl/hcalls.c
>   create mode 100644 drivers/misc/cxl/hcalls.h
>
> diff --git a/drivers/misc/cxl/cxl.h b/drivers/misc/cxl/cxl.h
> index c7ed265..ac655a6 100644
> --- a/drivers/misc/cxl/cxl.h
> +++ b/drivers/misc/cxl/cxl.h
> @@ -688,6 +688,7 @@ void cxl_prefault(struct cxl_context *ctx, u64 wed);
>
>   struct cxl *get_cxl_adapter(int num);
>   int cxl_alloc_sst(struct cxl_context *ctx);
> +void cxl_dump_debug_buffer(void *addr, size_t size);
>
>   void init_cxl_native(void);
>
> @@ -701,16 +702,34 @@ unsigned int cxl_map_irq(struct cxl *adapter, irq_hw_number_t hwirq,
>   void cxl_unmap_irq(unsigned int virq, void *cookie);
>   int __detach_context(struct cxl_context *ctx);
>
> -/* This matches the layout of the H_COLLECT_CA_INT_INFO retbuf */
> +/*
> + * This must match the layout of the H_COLLECT_CA_INT_INFO retbuf defined
> + * in PAPR.
> + * A word about endianness: a pointer to this structure is passed when
> + * calling the hcall. However, it is not a block of memory filled up by
> + * the hypervisor. The return values are found in registers, and copied
> + * one by one when returning from the hcall. See the end of the call to
> + * plpar_hcall9() in hvCall.S
> + * As a consequence:
> + * - we don't need to do any endianness conversion
> + * - the pid and tid are an exception. They are 32-bit values returned in
> + *   the same 64-bit register. So we do need to worry about byte ordering.
> + */
>   struct cxl_irq_info {
>   	u64 dsisr;
>   	u64 dar;
>   	u64 dsr;
> +#ifndef CONFIG_CPU_LITTLE_ENDIAN
>   	u32 pid;
>   	u32 tid;
> +#else
> +	u32 tid;
> +	u32 pid;
> +#endif
>   	u64 afu_err;
>   	u64 errstat;
> -	u64 padding[3]; /* to match the expected retbuf size for plpar_hcall9 */
> +	u64 proc_handle;
> +	u64 padding[2]; /* to match the expected retbuf size for plpar_hcall9 */
>   };
>
>   void cxl_assign_psn_space(struct cxl_context *ctx);
> diff --git a/drivers/misc/cxl/hcalls.c b/drivers/misc/cxl/hcalls.c
> new file mode 100644
> index 0000000..7e4c517
> --- /dev/null
> +++ b/drivers/misc/cxl/hcalls.c
> @@ -0,0 +1,639 @@
> +/*
> + * Copyright 2015 IBM Corp.
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * as published by the Free Software Foundation; either version
> + * 2 of the License, or (at your option) any later version.
> + */
> +
> +
> +#include <linux/compiler.h>
> +#include <linux/types.h>
> +#include <linux/delay.h>
> +#include <asm/hvcall.h>
> +#include <asm/byteorder.h>
> +#include "hcalls.h"
> +
> +#define CXL_HCALL_TIMEOUT 60000
> +#define CXL_HCALL_TIMEOUT_DOWNLOAD 120000
> +
> +#define H_ATTACH_CA_PROCESS    0x344
> +#define H_CONTROL_CA_FUNCTION  0x348
> +#define H_DETACH_CA_PROCESS    0x34C
> +#define H_COLLECT_CA_INT_INFO  0x350
> +#define H_CONTROL_CA_FAULTS    0x354
> +#define H_DOWNLOAD_CA_FUNCTION 0x35C
> +#define H_DOWNLOAD_CA_FACILITY 0x364
> +#define H_CONTROL_CA_FACILITY  0x368
> +
> +#define H_CONTROL_CA_FUNCTION_RESET                   1 /* perform a reset */
> +#define H_CONTROL_CA_FUNCTION_SUSPEND_PROCESS         2 /* suspend a process from being executed */
> +#define H_CONTROL_CA_FUNCTION_RESUME_PROCESS          3 /* resume a process to be executed */
> +#define H_CONTROL_CA_FUNCTION_READ_ERR_STATE          4 /* read the error state */
> +#define H_CONTROL_CA_FUNCTION_GET_AFU_ERR             5 /* collect the AFU error buffer */
> +#define H_CONTROL_CA_FUNCTION_GET_CONFIG              6 /* collect configuration record */
> +#define H_CONTROL_CA_FUNCTION_GET_DOWNLOAD_STATE      7 /* query to return download status */
> +#define H_CONTROL_CA_FUNCTION_TERMINATE_PROCESS       8 /* terminate the process before completion */
> +#define H_CONTROL_CA_FUNCTION_COLLECT_VPD             9 /* collect VPD */
> +#define H_CONTROL_CA_FUNCTION_GET_FUNCTION_ERR_INT   11 /* read the function-wide error data based on an interrupt */
> +#define H_CONTROL_CA_FUNCTION_ACK_FUNCTION_ERR_INT   12 /* acknowledge function-wide error data based on an interrupt */
> +#define H_CONTROL_CA_FUNCTION_GET_ERROR_LOG          13 /* retrieve the Platform Log ID (PLID) of an error log */
> +
> +#define H_CONTROL_CA_FAULTS_RESPOND_PSL         1
> +#define H_CONTROL_CA_FAULTS_RESPOND_AFU         2
> +
> +#define H_CONTROL_CA_FACILITY_RESET             1 /* perform a reset */
> +#define H_CONTROL_CA_FACILITY_COLLECT_VPD       2 /* collect VPD */
> +
> +#define H_DOWNLOAD_CA_FACILITY_DOWNLOAD         1 /* download adapter image */
> +#define H_DOWNLOAD_CA_FACILITY_VALIDATE         2 /* validate adapter image */
> +
> +
> +#define _CXL_LOOP_HCALL(call, rc, retbuf, fn, ...)			\
> +	{								\
> +		unsigned int delay, total_delay = 0;			\
> +		u64 token = 0;						\
> +									\
> +		memset(retbuf, 0, sizeof(retbuf));			\
> +		while (1) {						\
> +			rc = call(fn, retbuf, __VA_ARGS__, token);	\
> +			token = retbuf[0];				\
> +			if (rc != H_BUSY && !H_IS_LONG_BUSY(rc))	\
> +				break;					\
> +									\
> +			if (rc == H_BUSY)				\
> +				delay = 10;				\
> +			else						\
> +				delay = get_longbusy_msecs(rc);		\
> +									\
> +			total_delay += delay;				\
> +			if (total_delay > CXL_HCALL_TIMEOUT) {		\
> +				WARN(1, "Warning: Giving up waiting for CXL hcall " \
> +					"%#x after %u msec\n", fn, total_delay); \
> +				rc = H_BUSY;				\
> +				break;					\
> +			}						\
> +			msleep(delay);					\
> +		}							\
> +	}
> +#define CXL_H_WAIT_UNTIL_DONE(...)  _CXL_LOOP_HCALL(plpar_hcall, __VA_ARGS__)
> +#define CXL_H9_WAIT_UNTIL_DONE(...) _CXL_LOOP_HCALL(plpar_hcall9, __VA_ARGS__)
> +
> +#define _PRINT_MSG(rc, format, ...)					\
> +	{								\
> +		if ((rc != H_SUCCESS) && (rc != H_CONTINUE))		\
> +			pr_err(format, __VA_ARGS__);			\
> +		else							\
> +			pr_devel(format, __VA_ARGS__);			\
> +	}								\
> +
> +
> +static char *afu_op_names[] = {
> +	"UNKNOWN_OP",		/* 0 undefined */
> +	"RESET",		/* 1 */
> +	"SUSPEND_PROCESS",	/* 2 */
> +	"RESUME_PROCESS",	/* 3 */
> +	"READ_ERR_STATE",	/* 4 */
> +	"GET_AFU_ERR",		/* 5 */
> +	"GET_CONFIG",		/* 6 */
> +	"GET_DOWNLOAD_STATE",	/* 7 */
> +	"TERMINATE_PROCESS",	/* 8 */
> +	"COLLECT_VPD",		/* 9 */
> +	"UNKNOWN_OP",		/* 10 undefined */
> +	"GET_FUNCTION_ERR_INT",	/* 11 */
> +	"ACK_FUNCTION_ERR_INT",	/* 12 */
> +	"GET_ERROR_LOG",	/* 13 */
> +};
> +
> +static char *control_adapter_op_names[] = {
> +	"UNKNOWN_OP",		/* 0 undefined */
> +	"RESET",		/* 1 */
> +	"COLLECT_VPD",		/* 2 */
> +};
> +
> +static char *download_op_names[] = {
> +	"UNKNOWN_OP",		/* 0 undefined */
> +	"DOWNLOAD",		/* 1 */
> +	"VALIDATE",		/* 2 */
> +};
> +
> +static char *op_str(unsigned int op, char *name_array[], int array_len)
> +{
> +	if (op >= array_len)
> +		return "UNKNOWN_OP";
> +	return name_array[op];
> +}
> +
> +#define OP_STR(op, name_array)      op_str(op, name_array, ARRAY_SIZE(name_array))
> +
> +#define OP_STR_AFU(op)              OP_STR(op, afu_op_names)
> +#define OP_STR_CONTROL_ADAPTER(op)  OP_STR(op, control_adapter_op_names)
> +#define OP_STR_DOWNLOAD_ADAPTER(op) OP_STR(op, download_op_names)
> +
> +
> +long cxl_h_attach_process(u64 unit_address,
> +			struct cxl_process_element_hcall *element,
> +			u64 *process_token, u64 *mmio_addr, u64 *mmio_size)
> +{
> +	unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
> +	long rc;
> +
> +	CXL_H_WAIT_UNTIL_DONE(rc, retbuf, H_ATTACH_CA_PROCESS, unit_address, virt_to_phys(element));
> +	_PRINT_MSG(rc, "cxl_h_attach_process(%#.16llx, %#.16lx): %li\n",
> +		unit_address, virt_to_phys(element), rc);
> +
> +	pr_devel("token: 0x%.8lx mmio_addr: 0x%lx mmio_size: 0x%lx\nProcess Element Structure:\n",
> +		retbuf[0], retbuf[1], retbuf[2]);
> +	cxl_dump_debug_buffer(element, sizeof(*element));
> +
> +	switch (rc) {
> +	case H_SUCCESS:       /* The process info is attached to the coherent platform function */
> +		*process_token = retbuf[0];
> +		if (mmio_addr)
> +			*mmio_addr = retbuf[1];
> +		if (mmio_size)
> +			*mmio_size = retbuf[2];
> +		return 0;
> +	case H_PARAMETER:     /* An incorrect parameter was supplied. */
> +	case H_FUNCTION:      /* The function is not supported. */
> +		return -EINVAL;
> +	case H_AUTHORITY:     /* The partition does not have authority to perform this hcall */
> +	case H_RESOURCE:      /* The coherent platform function does not have enough additional resource to attach the process */
> +	case H_HARDWARE:      /* A hardware event prevented the attach operation */
> +	case H_STATE:         /* The coherent platform function is not in a valid state */
> +	case H_BUSY:
> +		return -EBUSY;
> +	default:
> +		WARN(1, "Unexpected return code: %lx", rc);
> +		return -EINVAL;
> +	}
> +}
> +
> +/**
> + * cxl_h_detach_process - Detach a process element from a coherent
> + *                        platform function.
> + */
> +long cxl_h_detach_process(u64 unit_address, u64 process_token)
> +{
> +	unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
> +	long rc;
> +
> +	CXL_H_WAIT_UNTIL_DONE(rc, retbuf, H_DETACH_CA_PROCESS, unit_address, process_token);
> +	_PRINT_MSG(rc, "cxl_h_detach_process(%#.16llx, 0x%.8llx): %li\n", unit_address, process_token, rc);
> +
> +	switch (rc) {
> +	case H_SUCCESS:       /* The process was detached from the coherent platform function */
> +		return 0;
> +	case H_PARAMETER:     /* An incorrect parameter was supplied. */
> +		return -EINVAL;
> +	case H_AUTHORITY:     /* The partition does not have authority to perform this hcall */
> +	case H_RESOURCE:      /* The function has page table mappings for MMIO */
> +	case H_HARDWARE:      /* A hardware event prevented the detach operation */
> +	case H_STATE:         /* The coherent platform function is not in a valid state */
> +	case H_BUSY:
> +		return -EBUSY;
> +	default:
> +		WARN(1, "Unexpected return code: %lx", rc);
> +		return -EINVAL;
> +	}
> +}
> +
> +/**
> + * cxl_h_control_function - This H_CONTROL_CA_FUNCTION hypervisor call allows
> + *                          the partition to manipulate or query
> + *                          certain coherent platform function behaviors.
> + */
> +static long cxl_h_control_function(u64 unit_address, u64 op,
> +				   u64 p1, u64 p2, u64 p3, u64 p4, u64 *out)
> +{
> +	unsigned long retbuf[PLPAR_HCALL9_BUFSIZE];
> +	long rc;
> +
> +	CXL_H9_WAIT_UNTIL_DONE(rc, retbuf, H_CONTROL_CA_FUNCTION, unit_address, op, p1, p2, p3, p4);
> +	_PRINT_MSG(rc, "cxl_h_control_function(%#.16llx, %s(%#llx, %#llx, %#llx, %#llx, R4: %#lx)): %li\n",
> +		unit_address, OP_STR_AFU(op), p1, p2, p3, p4, retbuf[0], rc);
> +
> +	switch (rc) {
> +	case H_SUCCESS:       /* The operation is completed for the coherent platform function */
> +		if ((op == H_CONTROL_CA_FUNCTION_GET_FUNCTION_ERR_INT ||
> +		     op == H_CONTROL_CA_FUNCTION_READ_ERR_STATE ||
> +		     op == H_CONTROL_CA_FUNCTION_COLLECT_VPD))
> +			*out = retbuf[0];
> +		return 0;
> +	case H_PARAMETER:     /* An incorrect parameter was supplied. */
> +	case H_FUNCTION:      /* The function is not supported. */
> +	case H_NOT_FOUND:     /* The operation supplied was not valid */
> +	case H_NOT_AVAILABLE: /* The operation cannot be performed because the AFU has not been downloaded */
> +	case H_SG_LIST:       /* An block list entry was invalid */
> +		return -EINVAL;
> +	case H_AUTHORITY:     /* The partition does not have authority to perform this hcall */
> +	case H_RESOURCE:      /* The function has page table mappings for MMIO */
> +	case H_HARDWARE:      /* A hardware event prevented the attach operation */
> +	case H_STATE:         /* The coherent platform function is not in a valid state */
> +	case H_BUSY:
> +		return -EBUSY;
> +	default:
> +		WARN(1, "Unexpected return code: %lx", rc);
> +		return -EINVAL;
> +	}
> +}
> +
> +/**
> + * cxl_h_reset_afu - Perform a reset to the coherent platform function.
> + */
> +long cxl_h_reset_afu(u64 unit_address)
> +{
> +	return cxl_h_control_function(unit_address,
> +				H_CONTROL_CA_FUNCTION_RESET,
> +				0, 0, 0, 0,
> +				NULL);
> +}
> +
> +/**
> + * cxl_h_suspend_process - Suspend a process from being executed
> + * Parameter1 = process-token as returned from H_ATTACH_CA_PROCESS when
> + *              process was attached.
> + */
> +long cxl_h_suspend_process(u64 unit_address, u64 process_token)
> +{
> +	return cxl_h_control_function(unit_address,
> +				H_CONTROL_CA_FUNCTION_SUSPEND_PROCESS,
> +				process_token, 0, 0, 0,
> +				NULL);
> +}
> +
> +/**
> + * cxl_h_resume_process - Resume a process to be executed
> + * Parameter1 = process-token as returned from H_ATTACH_CA_PROCESS when
> + *              process was attached.
> + */
> +long cxl_h_resume_process(u64 unit_address, u64 process_token)
> +{
> +	return cxl_h_control_function(unit_address,
> +				H_CONTROL_CA_FUNCTION_RESUME_PROCESS,
> +				process_token, 0, 0, 0,
> +				NULL);
> +}
> +
> +/**
> + * cxl_h_read_error_state - Checks the error state of the coherent
> + *                          platform function.
> + * R4 contains the error state
> + */
> +long cxl_h_read_error_state(u64 unit_address, u64 *state)
> +{
> +	return cxl_h_control_function(unit_address,
> +				H_CONTROL_CA_FUNCTION_READ_ERR_STATE,
> +				0, 0, 0, 0,
> +				state);
> +}
> +
> +/**
> + * cxl_h_get_afu_err - collect the AFU error buffer
> + * Parameter1 = byte offset into error buffer to retrieve, valid values
> + *              are between 0 and (ibm,error-buffer-size - 1)
> + * Parameter2 = 4K aligned real address of error buffer, to be filled in
> + * Parameter3 = length of error buffer, valid values are 4K or less
> + */
> +long cxl_h_get_afu_err(u64 unit_address, u64 offset,
> +		u64 buf_address, u64 len)
> +{
> +	return cxl_h_control_function(unit_address,
> +				H_CONTROL_CA_FUNCTION_GET_AFU_ERR,
> +				offset, buf_address, len, 0,
> +				NULL);
> +}
> +
> +/**
> + * cxl_h_get_config - collect configuration record for the
> + *                    coherent platform function
> + * Parameter1 = # of configuration record to retrieve, valid values are
> + *              between 0 and (ibm,#config-records - 1)
> + * Parameter2 = byte offset into configuration record to retrieve,
> + *              valid values are between 0 and (ibm,config-record-size - 1)
> + * Parameter3 = 4K aligned real address of configuration record buffer,
> + *              to be filled in
> + * Parameter4 = length of configuration buffer, valid values are 4K or less
> + */
> +long cxl_h_get_config(u64 unit_address, u64 cr_num, u64 offset,
> +		u64 buf_address, u64 len)
> +{
> +	return cxl_h_control_function(unit_address,
> +				H_CONTROL_CA_FUNCTION_GET_CONFIG,
> +				cr_num, offset, buf_address, len,
> +				NULL);
> +}
> +
> +/**
> + * cxl_h_terminate_process - Terminate the process before completion
> + * Parameter1 = process-token as returned from H_ATTACH_CA_PROCESS when
> + *              process was attached.
> + */
> +long cxl_h_terminate_process(u64 unit_address, u64 process_token)
> +{
> +	return cxl_h_control_function(unit_address,
> +				H_CONTROL_CA_FUNCTION_TERMINATE_PROCESS,
> +				process_token, 0, 0, 0,
> +				NULL);
> +}
> +
> +/**
> + * cxl_h_collect_vpd - Collect VPD for the coherent platform function.
> + * Parameter1 = # of VPD record to retrieve, valid values are between 0
> + *              and (ibm,#config-records - 1).
> + * Parameter2 = 4K naturally aligned real buffer containing block
> + *              list entries
> + * Parameter3 = number of block list entries in the block list, valid
> + *              values are between 0 and 256
> + */
> +long cxl_h_collect_vpd(u64 unit_address, u64 record, u64 list_address,
> +		       u64 num, u64 *out)
> +{
> +	return cxl_h_control_function(unit_address,
> +				H_CONTROL_CA_FUNCTION_COLLECT_VPD,
> +				record, list_address, num, 0,
> +				out);
> +}
> +
> +/**
> + * cxl_h_get_fn_error_interrupt - Read the function-wide error data based on an interrupt
> + */
> +long cxl_h_get_fn_error_interrupt(u64 unit_address, u64 *reg)
> +{
> +	return cxl_h_control_function(unit_address,
> +				H_CONTROL_CA_FUNCTION_GET_FUNCTION_ERR_INT,
> +				0, 0, 0, 0, reg);
> +}
> +
> +/**
> + * cxl_h_ack_fn_error_interrupt - Acknowledge function-wide error data
> + *                                based on an interrupt
> + * Parameter1 = value to write to the function-wide error interrupt register
> + */
> +long cxl_h_ack_fn_error_interrupt(u64 unit_address, u64 value)
> +{
> +	return cxl_h_control_function(unit_address,
> +				H_CONTROL_CA_FUNCTION_ACK_FUNCTION_ERR_INT,
> +				value, 0, 0, 0,
> +				NULL);
> +}
> +
> +/**
> + * cxl_h_get_error_log - Retrieve the Platform Log ID (PLID) of
> + *                       an error log
> + */
> +long cxl_h_get_error_log(u64 unit_address, u64 value)
> +{
> +	return cxl_h_control_function(unit_address,
> +				H_CONTROL_CA_FUNCTION_GET_ERROR_LOG,
> +				0, 0, 0, 0,
> +				NULL);
> +}
> +
> +/**
> + * cxl_h_collect_int_info - Collect interrupt info about a coherent
> + *                          platform function after an interrupt occurred.
> + */
> +long cxl_h_collect_int_info(u64 unit_address, u64 process_token,
> +			    struct cxl_irq_info *info)
> +{
> +	long rc;
> +
> +	BUG_ON(sizeof(*info) != sizeof(unsigned long[PLPAR_HCALL9_BUFSIZE]));
> +
> +	rc = plpar_hcall9(H_COLLECT_CA_INT_INFO, (unsigned long *) info,
> +			unit_address, process_token);
> +	_PRINT_MSG(rc, "cxl_h_collect_int_info(%#.16llx, 0x%llx): %li\n",
> +		unit_address, process_token, rc);
> +
> +	switch (rc) {
> +	case H_SUCCESS:     /* The interrupt info is returned in return registers. */
> +		pr_devel("dsisr:%#llx, dar:%#llx, dsr:%#llx, pid:%u, tid:%u, afu_err:%#llx, errstat:%#llx\n",
> +			info->dsisr, info->dar, info->dsr, info->pid,
> +			info->tid, info->afu_err, info->errstat);
> +		return 0;
> +	case H_PARAMETER:   /* An incorrect parameter was supplied. */
> +		return -EINVAL;
> +	case H_AUTHORITY:   /* The partition does not have authority to perform this hcall. */
> +	case H_HARDWARE:    /* A hardware event prevented the collection of the interrupt info.*/
> +	case H_STATE:       /* The coherent platform function is not in a valid state to collect interrupt info. */
> +		return -EBUSY;
> +	default:
> +		WARN(1, "Unexpected return code: %lx", rc);
> +		return -EINVAL;
> +	}
> +}
> +
> +/**
> + * cxl_h_control_faults - Control the operation of a coherent platform
> + *                        function after a fault occurs.
> + *
> + * Parameters
> + *    control-mask: value to control the faults
> + *                  looks like PSL_TFC_An shifted >> 32
> + *    reset-mask: mask to control reset of function faults
> + *                Set reset_mask = 1 to reset PSL errors
> + */
> +long cxl_h_control_faults(u64 unit_address, u64 process_token,
> +			  u64 control_mask, u64 reset_mask)
> +{
> +	unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
> +	long rc;
> +
> +	memset(retbuf, 0, sizeof(retbuf));
> +
> +	rc = plpar_hcall(H_CONTROL_CA_FAULTS, retbuf, unit_address,
> +			H_CONTROL_CA_FAULTS_RESPOND_PSL, process_token,
> +			control_mask, reset_mask);
> +	_PRINT_MSG(rc, "cxl_h_control_faults(%#.16llx, 0x%llx, %#llx, %#llx): %li (%#lx)\n",
> +		unit_address, process_token, control_mask, reset_mask,
> +		rc, retbuf[0]);
> +
> +	switch (rc) {
> +	case H_SUCCESS:    /* Faults were successfully controlled for the function. */
> +		return 0;
> +	case H_PARAMETER:  /* An incorrect parameter was supplied. */
> +		return -EINVAL;
> +	case H_HARDWARE:   /* A hardware event prevented the control of faults. */
> +	case H_STATE:      /* The function was in an invalid state. */
> +	case H_AUTHORITY:  /* The partition does not have authority to perform this hcall; the coherent platform facilities may need to be licensed. */
> +		return -EBUSY;
> +	case H_FUNCTION:   /* The function is not supported */
> +	case H_NOT_FOUND:  /* The operation supplied was not valid */
> +		return -EINVAL;
> +	default:
> +		WARN(1, "Unexpected return code: %lx", rc);
> +		return -EINVAL;
> +	}
> +}
> +
> +/**
> + * cxl_h_control_facility - This H_CONTROL_CA_FACILITY hypervisor call
> + *                          allows the partition to manipulate or query
> + *                          certain coherent platform facility behaviors.
> + */
> +static long cxl_h_control_facility(u64 unit_address, u64 op,
> +				   u64 p1, u64 p2, u64 p3, u64 p4, u64 *out)
> +{
> +	unsigned long retbuf[PLPAR_HCALL9_BUFSIZE];
> +	long rc;
> +
> +	CXL_H9_WAIT_UNTIL_DONE(rc, retbuf, H_CONTROL_CA_FACILITY, unit_address, op, p1, p2, p3, p4);
> +	_PRINT_MSG(rc, "cxl_h_control_facility(%#.16llx, %s(%#llx, %#llx, %#llx, %#llx, R4: %#lx)): %li\n",
> +		unit_address, OP_STR_CONTROL_ADAPTER(op), p1, p2, p3, p4, retbuf[0], rc);
> +
> +	switch (rc) {
> +	case H_SUCCESS:       /* The operation is completed for the coherent platform facility */
> +		if (op == H_CONTROL_CA_FACILITY_COLLECT_VPD)
> +			*out = retbuf[0];
> +		return 0;
> +	case H_PARAMETER:     /* An incorrect parameter was supplied. */
> +	case H_FUNCTION:      /* The function is not supported. */
> +	case H_NOT_FOUND:     /* The operation supplied was not valid */
> +	case H_NOT_AVAILABLE: /* The operation cannot be performed because the AFU has not been downloaded */
> +	case H_SG_LIST:       /* An block list entry was invalid */
> +		return -EINVAL;
> +	case H_AUTHORITY:     /* The partition does not have authority to perform this hcall */
> +	case H_RESOURCE:      /* The function has page table mappings for MMIO */
> +	case H_HARDWARE:      /* A hardware event prevented the attach operation */
> +	case H_STATE:         /* The coherent platform facility is not in a valid state */
> +	case H_BUSY:
> +		return -EBUSY;
> +	default:
> +		WARN(1, "Unexpected return code: %lx", rc);
> +		return -EINVAL;
> +	}
> +}
> +
> +/**
> + * cxl_h_reset_adapter - Perform a reset to the coherent platform facility.
> + */
> +long cxl_h_reset_adapter(u64 unit_address)
> +{
> +	return cxl_h_control_facility(unit_address,
> +				H_CONTROL_CA_FACILITY_RESET,
> +				0, 0, 0, 0,
> +				NULL);
> +}
> +
> +/**
> + * cxl_h_collect_vpd - Collect VPD for the coherent platform function.
> + * Parameter1 = 4K naturally aligned real buffer containing block
> + *              list entries
> + * Parameter2 = number of block list entries in the block list, valid
> + *              values are between 0 and 256
> + */
> +long cxl_h_collect_vpd_adapter(u64 unit_address, u64 list_address,
> +			       u64 num, u64 *out)
> +{
> +	return cxl_h_control_facility(unit_address,
> +				H_CONTROL_CA_FACILITY_COLLECT_VPD,
> +				list_address, num, 0, 0,
> +				out);
> +}
> +
> +/**
> + * cxl_h_download_facility - This H_DOWNLOAD_CA_FACILITY
> + *                    hypervisor call provide platform support for
> + *                    downloading a base adapter image to the coherent
> + *                    platform facility, and for validating the entire
> + *                    image after the download.
> + * Parameters
> + *    op: operation to perform to the coherent platform function
> + *      Download: operation = 1, the base image in the coherent platform
> + *                               facility is first erased, and then
> + *                               programmed using the image supplied
> + *                               in the scatter/gather list.
> + *      Validate: operation = 2, the base image in the coherent platform
> + *                               facility is compared with the image
> + *                               supplied in the scatter/gather list.
> + *    list_address: 4K naturally aligned real buffer containing
> + *                  scatter/gather list entries.
> + *    num: number of block list entries in the scatter/gather list.
> + */
> +static long cxl_h_download_facility(u64 unit_address, u64 op,
> +				    u64 list_address, u64 num,
> +				    u64 *out)
> +{
> +	unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
> +	unsigned int delay, total_delay = 0;
> +	u64 token = 0;
> +	long rc;
> +
> +	if (*out != 0)
> +		token = *out;
> +
> +	memset(retbuf, 0, sizeof(retbuf));
> +	while (1) {
> +		rc = plpar_hcall(H_DOWNLOAD_CA_FACILITY, retbuf,
> +				 unit_address, op, list_address, num,
> +				 token);
> +		token = retbuf[0];
> +		if (rc != H_BUSY && !H_IS_LONG_BUSY(rc))
> +			break;
> +
> +		if (rc != H_BUSY) {
> +			delay = get_longbusy_msecs(rc);
> +			total_delay += delay;
> +			if (total_delay > CXL_HCALL_TIMEOUT_DOWNLOAD) {
> +				WARN(1, "Warning: Giving up waiting for CXL hcall "
> +					"%#x after %u msec\n",
> +					H_DOWNLOAD_CA_FACILITY, total_delay);
> +				rc = H_BUSY;
> +				break;
> +			}
> +			msleep(delay);
> +		}
> +	}
> +	_PRINT_MSG(rc, "cxl_h_download_facility(%#.16llx, %s(%#llx, %#llx), %#lx): %li\n",
> +		 unit_address, OP_STR_DOWNLOAD_ADAPTER(op), list_address, num, retbuf[0], rc);
> +
> +	switch (rc) {
> +	case H_SUCCESS:       /* The operation is completed for the coherent platform facility */
> +		return 0;
> +	case H_PARAMETER:     /* An incorrect parameter was supplied */
> +	case H_FUNCTION:      /* The function is not supported. */
> +	case H_SG_LIST:       /* An block list entry was invalid */
> +	case H_BAD_DATA:      /* Image verification failed */
> +		return -EINVAL;
> +	case H_AUTHORITY:     /* The partition does not have authority to perform this hcall */
> +	case H_RESOURCE:      /* The function has page table mappings for MMIO */
> +	case H_HARDWARE:      /* A hardware event prevented the attach operation */
> +	case H_STATE:         /* The coherent platform facility is not in a valid state */
> +	case H_BUSY:
> +		return -EBUSY;
> +	case H_CONTINUE:
> +		*out = retbuf[0];
> +		return 1;  /* More data is needed for the complete image */
> +	default:
> +		WARN(1, "Unexpected return code: %lx", rc);
> +		return -EINVAL;
> +	}
> +}
> +
> +/**
> + * cxl_h_download_adapter_image - Download the base image to the coherent
> + *                                platform facility.
> + */
> +long cxl_h_download_adapter_image(u64 unit_address,
> +				  u64 list_address, u64 num,
> +				  u64 *out)
> +{
> +	return cxl_h_download_facility(unit_address,
> +				       H_DOWNLOAD_CA_FACILITY_DOWNLOAD,
> +				       list_address, num, out);
> +}
> +
> +/**
> + * cxl_h_validate_adapter_image - Validate the base image in the coherent
> + *                                platform facility.
> + */
> +long cxl_h_validate_adapter_image(u64 unit_address,
> +				  u64 list_address, u64 num,
> +				  u64 *out)
> +{
> +	return cxl_h_download_facility(unit_address,
> +				       H_DOWNLOAD_CA_FACILITY_VALIDATE,
> +				       list_address, num, out);
> +}
> diff --git a/drivers/misc/cxl/hcalls.h b/drivers/misc/cxl/hcalls.h
> new file mode 100644
> index 0000000..6bfab32
> --- /dev/null
> +++ b/drivers/misc/cxl/hcalls.h
> @@ -0,0 +1,203 @@
> +/*
> + * Copyright 2015 IBM Corp.
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * as published by the Free Software Foundation; either version
> + * 2 of the License, or (at your option) any later version.
> + */
> +
> +#ifndef _HCALLS_H
> +#define _HCALLS_H
> +
> +#include <linux/types.h>
> +#include <asm/byteorder.h>
> +#include "cxl.h"
> +
> +#define SG_BUFFER_SIZE 4096
> +#define SG_MAX_ENTRIES 256
> +
> +struct sg_list {
> +	u64 phys_addr;
> +	u64 len;
> +};
> +
> +/*
> + * This is straight out of PAPR, but replacing some of the compound fields with
> + * a single field, where they were identical to the register layout.
> + *
> + * The 'flags' parameter regroups the various bit-fields
> + */
> +#define CXL_PE_CSRP_VALID			(1ULL << 63)
> +#define CXL_PE_PROBLEM_STATE			(1ULL << 62)
> +#define CXL_PE_SECONDARY_SEGMENT_TBL_SRCH	(1ULL << 61)
> +#define CXL_PE_TAGS_ACTIVE			(1ULL << 60)
> +#define CXL_PE_USER_STATE			(1ULL << 59)
> +#define CXL_PE_TRANSLATION_ENABLED		(1ULL << 58)
> +#define CXL_PE_64_BIT				(1ULL << 57)
> +#define CXL_PE_PRIVILEGED_PROCESS		(1ULL << 56)
> +
> +#define CXL_PROCESS_ELEMENT_VERSION 1
> +struct cxl_process_element_hcall {
> +	__be64 version;
> +	__be64 flags;
> +	u8     reserved0[12];
> +	__be32 pslVirtualIsn;
> +	u8     applicationVirtualIsnBitmap[256];
> +	u8     reserved1[144];
> +	struct cxl_process_element_common common;
> +	u8     reserved4[12];
> +} __packed;
> +
> +#define H_STATE_NORMAL              1
> +#define H_STATE_DISABLE             2
> +#define H_STATE_TEMP_UNAVAILABLE    3
> +#define H_STATE_PERM_UNAVAILABLE    4
> +
> +/* NOTE: element must be a logical real address, and must be pinned */
> +long cxl_h_attach_process(u64 unit_address, struct cxl_process_element_hcall *element,
> +			u64 *process_token, u64 *mmio_addr, u64 *mmio_size);
> +
> +/**
> + * cxl_h_detach_process - Detach a process element from a coherent
> + *                        platform function.
> + */
> +long cxl_h_detach_process(u64 unit_address, u64 process_token);
> +
> +/**
> + * cxl_h_reset_afu - Perform a reset to the coherent platform function.
> + */
> +long cxl_h_reset_afu(u64 unit_address);
> +
> +/**
> + * cxl_h_suspend_process - Suspend a process from being executed
> + * Parameter1 = process-token as returned from H_ATTACH_CA_PROCESS when
> + *              process was attached.
> + */
> +long cxl_h_suspend_process(u64 unit_address, u64 process_token);
> +
> +/**
> + * cxl_h_resume_process - Resume a process to be executed
> + * Parameter1 = process-token as returned from H_ATTACH_CA_PROCESS when
> + *              process was attached.
> + */
> +long cxl_h_resume_process(u64 unit_address, u64 process_token);
> +
> +/**
> + * cxl_h_read_error_state - Reads the error state of the coherent
> + *                          platform function.
> + * R4 contains the error state
> + */
> +long cxl_h_read_error_state(u64 unit_address, u64 *state);
> +
> +/**
> + * cxl_h_get_afu_err - collect the AFU error buffer
> + * Parameter1 = byte offset into error buffer to retrieve, valid values
> + *              are between 0 and (ibm,error-buffer-size - 1)
> + * Parameter2 = 4K aligned real address of error buffer, to be filled in
> + * Parameter3 = length of error buffer, valid values are 4K or less
> + */
> +long cxl_h_get_afu_err(u64 unit_address, u64 offset, u64 buf_address, u64 len);
> +
> +/**
> + * cxl_h_get_config - collect configuration record for the
> + *                    coherent platform function
> + * Parameter1 = # of configuration record to retrieve, valid values are
> + *              between 0 and (ibm,#config-records - 1)
> + * Parameter2 = byte offset into configuration record to retrieve,
> + *              valid values are between 0 and (ibm,config-record-size - 1)
> + * Parameter3 = 4K aligned real address of configuration record buffer,
> + *              to be filled in
> + * Parameter4 = length of configuration buffer, valid values are 4K or less
> + */
> +long cxl_h_get_config(u64 unit_address, u64 cr_num, u64 offset,
> +		u64 buf_address, u64 len);
> +
> +/**
> + * cxl_h_terminate_process - Terminate the process before completion
> + * Parameter1 = process-token as returned from H_ATTACH_CA_PROCESS when
> + *              process was attached.
> + */
> +long cxl_h_terminate_process(u64 unit_address, u64 process_token);
> +
> +/**
> + * cxl_h_collect_vpd - Collect VPD for the coherent platform function.
> + * Parameter1 = # of VPD record to retrieve, valid values are between 0
> + *              and (ibm,#config-records - 1).
> + * Parameter2 = 4K naturally aligned real buffer containing block
> + *              list entries
> + * Parameter3 = number of block list entries in the block list, valid
> + *              values are between 0 and 256
> + */
> +long cxl_h_collect_vpd(u64 unit_address, u64 record, u64 list_address,
> +		       u64 num, u64 *out);
> +
> +/**
> + * cxl_h_get_fn_error_interrupt - Read the function-wide error data based on an interrupt
> + */
> +long cxl_h_get_fn_error_interrupt(u64 unit_address, u64 *reg);
> +
> +/**
> + * cxl_h_ack_fn_error_interrupt - Acknowledge function-wide error data
> + *                                based on an interrupt
> + * Parameter1 = value to write to the function-wide error interrupt register
> + */
> +long cxl_h_ack_fn_error_interrupt(u64 unit_address, u64 value);
> +
> +/**
> + * cxl_h_get_error_log - Retrieve the Platform Log ID (PLID) of
> + *                       an error log
> + */
> +long cxl_h_get_error_log(u64 unit_address, u64 value);
> +
> +/**
> + * cxl_h_collect_int_info - Collect interrupt info about a coherent
> + *                          platform function after an interrupt occurred.
> + */
> +long cxl_h_collect_int_info(u64 unit_address, u64 process_token,
> +			struct cxl_irq_info *info);
> +
> +/**
> + * cxl_h_control_faults - Control the operation of a coherent platform
> + *                        function after a fault occurs.
> + *
> + * Parameters
> + *    control-mask: value to control the faults
> + *                  looks like PSL_TFC_An shifted >> 32
> + *    reset-mask: mask to control reset of function faults
> + *                Set reset_mask = 1 to reset PSL errors
> + */
> +long cxl_h_control_faults(u64 unit_address, u64 process_token,
> +			u64 control_mask, u64 reset_mask);
> +
> +/**
> + * cxl_h_reset_adapter - Perform a reset to the coherent platform facility.
> + */
> +long cxl_h_reset_adapter(u64 unit_address);
> +
> +/**
> + * cxl_h_collect_vpd - Collect VPD for the coherent platform function.
> + * Parameter1 = 4K naturally aligned real buffer containing block
> + *              list entries
> + * Parameter2 = number of block list entries in the block list, valid
> + *              values are between 0 and 256
> + */
> +long cxl_h_collect_vpd_adapter(u64 unit_address, u64 list_address,
> +			       u64 num, u64 *out);
> +
> +/**
> + * cxl_h_download_adapter_image - Download the base image to the coherent
> + *                                platform facility.
> + */
> +long cxl_h_download_adapter_image(u64 unit_address,
> +				  u64 list_address, u64 num,
> +				  u64 *out);
> +
> +/**
> + * cxl_h_validate_adapter_image - Validate the base image in the coherent
> + *                                platform facility.
> + */
> +long cxl_h_validate_adapter_image(u64 unit_address,
> +				  u64 list_address, u64 num,
> +				  u64 *out);
> +#endif /* _HCALLS_H */
> diff --git a/drivers/misc/cxl/main.c b/drivers/misc/cxl/main.c
> index a9051512..814257b 100644
> --- a/drivers/misc/cxl/main.c
> +++ b/drivers/misc/cxl/main.c
> @@ -162,6 +162,32 @@ int cxl_alloc_sst(struct cxl_context *ctx)
>   	return 0;
>   }
>
> +/* print buffer content as integers when debugging */
> +void cxl_dump_debug_buffer(void *buf, size_t buf_len)
> +{
> +#ifdef DEBUG
> +	int i, *ptr;
> +
> +	/*
> +	 * We want to regroup up to 4 integers per line, which means they
> +	 * need to be in the same pr_devel() statement
> +	 */
> +	ptr = (int *) buf;
> +	for (i = 0; i * 4 < buf_len; i += 4) {
> +		if ((i + 3) * 4 < buf_len)
> +			pr_devel("%.8x %.8x %.8x %.8x\n", ptr[i], ptr[i + 1],
> +				ptr[i + 2], ptr[i + 3]);
> +		else if ((i + 2) * 4 < buf_len)
> +			pr_devel("%.8x %.8x %.8x\n", ptr[i], ptr[i + 1],
> +				ptr[i + 2]);
> +		else if ((i + 1) * 4 < buf_len)
> +			pr_devel("%.8x %.8x\n", ptr[i], ptr[i + 1]);
> +		else
> +			pr_devel("%.8x\n", ptr[i]);
> +	}
> +#endif /* DEBUG */
> +}
> +
>   /* Find a CXL adapter by it's number and increase it's refcount */
>   struct cxl *get_cxl_adapter(int num)
>   {
> diff --git a/drivers/misc/cxl/native.c b/drivers/misc/cxl/native.c
> index b8a6ad5..7d52629 100644
> --- a/drivers/misc/cxl/native.c
> +++ b/drivers/misc/cxl/native.c
> @@ -726,6 +726,7 @@ static int native_get_irq_info(struct cxl_afu *afu, struct cxl_irq_info *info)
>   	info->tid = pidtid & 0xffffffff;
>   	info->afu_err = cxl_p2n_read(afu, CXL_AFU_ERR_An);
>   	info->errstat = cxl_p2n_read(afu, CXL_PSL_ErrStat_An);
> +	info->proc_handle = 0;
>
>   	return 0;
>   }
>