Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 594ff7d0 authored by Christophe Lombard's avatar Christophe Lombard Committed by Michael Ellerman
Browse files

cxl: Support to flash a new image on the adapter from a guest 



The new flash.c file contains the logic to flash a new image on the
adapter, through a hcall. It is an iterative process, with chunks of
data of 1M at a time. There are also 2 phases: write and verify. The
flash operation itself is driven from a user-land tool.
Once flashing is successful, an rtas call is made to update the device
tree with the new properties values for the adapter and the AFU(s)

Add a new char device for the adapter, so that the flash tool can
access the card, even if there is no valid AFU on it.

Co-authored-by: default avatarFrederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: default avatarFrederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: default avatarChristophe Lombard <clombard@linux.vnet.ibm.com>
Reviewed-by: default avatarManoj Kumar <manoj@linux.vnet.ibm.com>
Acked-by: default avatarIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
parent 4752876c

Documentation/powerpc/cxl.txt

+55 −0
Original line number Diff line number Diff line
@@ -116,6 +116,8 @@ Work Element Descriptor (WED) 
User API

========



1. AFU character devices



    For AFUs operating in AFU directed mode, two character device

    files will be created. /dev/cxl/afu0.0m will correspond to a

    master context and /dev/cxl/afu0.0s will correspond to a slave
@@ -362,6 +364,59 @@ read 
        reserved fields:

            For future extensions and padding





2. Card character device (powerVM guest only)



    In a powerVM guest, an extra character device is created for the

    card. The device is only used to write (flash) a new image on the

    FPGA accelerator. Once the image is written and verified, the

    device tree is updated and the card is reset to reload the updated

    image.



open

----



    Opens the device and allocates a file descriptor to be used with

    the rest of the API. The device can only be opened once.



ioctl

-----



CXL_IOCTL_DOWNLOAD_IMAGE:

CXL_IOCTL_VALIDATE_IMAGE:

    Starts and controls flashing a new FPGA image. Partial

    reconfiguration is not supported (yet), so the image must contain

    a copy of the PSL and AFU(s). Since an image can be quite large,

    the caller may have to iterate, splitting the image in smaller

    chunks.



    Takes a pointer to a struct cxl_adapter_image:

        struct cxl_adapter_image {

            __u64 flags;

            __u64 data;

            __u64 len_data;

            __u64 len_image;

            __u64 reserved1;

            __u64 reserved2;

            __u64 reserved3;

            __u64 reserved4;

        };



    flags:

        These flags indicate which optional fields are present in

        this struct. Currently all fields are mandatory.



    data:

        Pointer to a buffer with part of the image to write to the

        card.



    len_data:

        Size of the buffer pointed to by data.



    len_image:

        Full size of the image.





Sysfs Class

===========

drivers/misc/cxl/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -4,7 +4,7 @@ ccflags-$(CONFIG_PPC_WERROR) += -Werror 
cxl-y				+= main.o file.o irq.o fault.o native.o

cxl-y				+= context.o sysfs.o debugfs.o pci.o trace.o

cxl-y				+= vphb.o api.o

cxl-$(CONFIG_PPC_PSERIES)	+= guest.o of.o hcalls.o

cxl-$(CONFIG_PPC_PSERIES)	+= flash.o guest.o of.o hcalls.o

obj-$(CONFIG_CXL)		+= cxl.o

obj-$(CONFIG_CXL_BASE)		+= base.o

drivers/misc/cxl/base.c

+7 −0
Original line number Diff line number Diff line
@@ -84,3 +84,10 @@ void unregister_cxl_calls(struct cxl_calls *calls) 
	synchronize_rcu();

}

EXPORT_SYMBOL_GPL(unregister_cxl_calls);



int cxl_update_properties(struct device_node *dn,

			  struct property *new_prop)

{

	return of_update_property(dn, new_prop);

}

EXPORT_SYMBOL_GPL(cxl_update_properties);

drivers/misc/cxl/cxl.h

+6 −0
Original line number Diff line number Diff line
@@ -324,6 +324,10 @@ static const cxl_p2n_reg_t CXL_PSL_WED_An = {0x0A0}; 
#define CXL_MODE_TIME_SLICED 0x4

#define CXL_SUPPORTED_MODES (CXL_MODE_DEDICATED | CXL_MODE_DIRECTED)



#define CXL_DEV_MINORS 13   /* 1 control + 4 AFUs * 3 (dedicated/master/shared) */

#define CXL_CARD_MINOR(adapter) (adapter->adapter_num * CXL_DEV_MINORS)

#define CXL_DEVT_ADAPTER(dev) (MINOR(dev) / CXL_DEV_MINORS)



enum cxl_context_status {

	CLOSED,

	OPENED,
@@ -692,12 +696,14 @@ struct cxl_calls { 
};

int register_cxl_calls(struct cxl_calls *calls);

void unregister_cxl_calls(struct cxl_calls *calls);

int cxl_update_properties(struct device_node *dn, struct property *new_prop);



void cxl_remove_adapter_nr(struct cxl *adapter);



int cxl_alloc_spa(struct cxl_afu *afu);

void cxl_release_spa(struct cxl_afu *afu);



dev_t cxl_get_dev(void);

int cxl_file_init(void);

void cxl_file_exit(void);

int cxl_register_adapter(struct cxl *adapter);

drivers/misc/cxl/file.c

+7 −4
Original line number Diff line number Diff line
@@ -26,9 +26,7 @@ 
#include "trace.h"



#define CXL_NUM_MINORS 256 /* Total to reserve */

#define CXL_DEV_MINORS 13   /* 1 control + 4 AFUs * 3 (dedicated/master/shared) */



#define CXL_CARD_MINOR(adapter) (adapter->adapter_num * CXL_DEV_MINORS)

#define CXL_AFU_MINOR_D(afu) (CXL_CARD_MINOR(afu->adapter) + 1 + (3 * afu->slice))

#define CXL_AFU_MINOR_M(afu) (CXL_AFU_MINOR_D(afu) + 1)

#define CXL_AFU_MINOR_S(afu) (CXL_AFU_MINOR_D(afu) + 2)
@@ -36,7 +34,6 @@ 
#define CXL_AFU_MKDEV_M(afu) MKDEV(MAJOR(cxl_dev), CXL_AFU_MINOR_M(afu))

#define CXL_AFU_MKDEV_S(afu) MKDEV(MAJOR(cxl_dev), CXL_AFU_MINOR_S(afu))



#define CXL_DEVT_ADAPTER(dev) (MINOR(dev) / CXL_DEV_MINORS)

#define CXL_DEVT_AFU(dev) ((MINOR(dev) % CXL_DEV_MINORS - 1) / 3)



#define CXL_DEVT_IS_CARD(dev) (MINOR(dev) % CXL_DEV_MINORS == 0)
@@ -446,7 +443,8 @@ static const struct file_operations afu_master_fops = { 


static char *cxl_devnode(struct device *dev, umode_t *mode)

{

	if (CXL_DEVT_IS_CARD(dev->devt)) {

	if (cpu_has_feature(CPU_FTR_HVMODE) &&

	    CXL_DEVT_IS_CARD(dev->devt)) {

		/*

		 * These minor numbers will eventually be used to program the

		 * PSL and AFUs once we have dynamic reprogramming support
@@ -547,6 +545,11 @@ int cxl_register_adapter(struct cxl *adapter) 
	return device_register(&adapter->dev);

}



dev_t cxl_get_dev(void)

{

	return cxl_dev;

}



int __init cxl_file_init(void)

{

	int rc;