Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Subject: Re: [PATCH 1/7] ocxl: Provide global MMIO accessors for external
 drivers
To:     "Alastair D'Silva" <alastair@au1.ibm.com>
Cc:     "Alastair D'Silva" <alastair@d-silva.org>,
        Greg Kurz <groug@kaod.org>,
        Frederic Barrat <fbarrat@linux.ibm.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org
References: <20190313041524.14644-1-alastair@au1.ibm.com>
 <20190313041524.14644-2-alastair@au1.ibm.com>
From:   Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Date:   Fri, 15 Mar 2019 15:11:16 +1100
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101
 Thunderbird/60.5.1
MIME-Version: 1.0
In-Reply-To: <20190313041524.14644-2-alastair@au1.ibm.com>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Language: en-AU
Content-Transfer-Encoding: 7bit
Message-Id: <0930a60a-05e1-ab6d-6568-2384bd1782ca@au1.ibm.com>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On 13/3/19 3:15 pm, Alastair D'Silva wrote:
> From: Alastair D'Silva <alastair@d-silva.org>
> 
> External drivers that communicate via OpenCAPI will need to make
> MMIO calls to interact with the devices.
> 
> Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
> Reviewed-by: Greg Kurz <groug@kaod.org>

Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>

> ---
>   drivers/misc/ocxl/Makefile |   2 +-
>   drivers/misc/ocxl/mmio.c   | 234 +++++++++++++++++++++++++++++++++++++
>   include/misc/ocxl.h        | 113 ++++++++++++++++++
>   3 files changed, 348 insertions(+), 1 deletion(-)
>   create mode 100644 drivers/misc/ocxl/mmio.c
> 
> diff --git a/drivers/misc/ocxl/Makefile b/drivers/misc/ocxl/Makefile
> index 5229dcda8297..922e47cd4f0d 100644
> --- a/drivers/misc/ocxl/Makefile
> +++ b/drivers/misc/ocxl/Makefile
> @@ -1,7 +1,7 @@
>   # SPDX-License-Identifier: GPL-2.0+
>   ccflags-$(CONFIG_PPC_WERROR)	+= -Werror
>   
> -ocxl-y				+= main.o pci.o config.o file.o pasid.o
> +ocxl-y				+= main.o pci.o config.o file.o pasid.o mmio.o
>   ocxl-y				+= link.o context.o afu_irq.o sysfs.o trace.o
>   obj-$(CONFIG_OCXL)		+= ocxl.o
>   
> diff --git a/drivers/misc/ocxl/mmio.c b/drivers/misc/ocxl/mmio.c
> new file mode 100644
> index 000000000000..7f6ebae1c6c7
> --- /dev/null
> +++ b/drivers/misc/ocxl/mmio.c
> @@ -0,0 +1,234 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +// Copyright 2017 IBM Corp.
> +#include <linux/sched/mm.h>
> +#include "trace.h"
> +#include "ocxl_internal.h"
> +
> +int ocxl_global_mmio_read32(struct ocxl_afu *afu, size_t offset,
> +				enum ocxl_endian endian, u32 *val)
> +{
> +	if (offset > afu->config.global_mmio_size - 4)
> +		return -EINVAL;
> +
> +#ifdef __BIG_ENDIAN__
> +	if (endian == OCXL_HOST_ENDIAN)
> +		endian = OCXL_BIG_ENDIAN;
> +#endif
> +
> +	switch (endian) {
> +	case OCXL_BIG_ENDIAN:
> +		*val = readl_be((char *)afu->global_mmio_ptr + offset);
> +		break;
> +
> +	default:
> +		*val = readl((char *)afu->global_mmio_ptr + offset);
> +		break;
> +	}
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(ocxl_global_mmio_read32);
> +
> +int ocxl_global_mmio_read64(struct ocxl_afu *afu, size_t offset,
> +				enum ocxl_endian endian, u64 *val)
> +{
> +	if (offset > afu->config.global_mmio_size - 8)
> +		return -EINVAL;
> +
> +#ifdef __BIG_ENDIAN__
> +	if (endian == OCXL_HOST_ENDIAN)
> +		endian = OCXL_BIG_ENDIAN;
> +#endif
> +
> +	switch (endian) {
> +	case OCXL_BIG_ENDIAN:
> +		*val = readq_be((char *)afu->global_mmio_ptr + offset);
> +		break;
> +
> +	default:
> +		*val = readq((char *)afu->global_mmio_ptr + offset);
> +		break;
> +	}
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(ocxl_global_mmio_read64);
> +
> +int ocxl_global_mmio_write32(struct ocxl_afu *afu, size_t offset,
> +				enum ocxl_endian endian, u32 val)
> +{
> +	if (offset > afu->config.global_mmio_size - 4)
> +		return -EINVAL;
> +
> +#ifdef __BIG_ENDIAN__
> +	if (endian == OCXL_HOST_ENDIAN)
> +		endian = OCXL_BIG_ENDIAN;
> +#endif
> +
> +	switch (endian) {
> +	case OCXL_BIG_ENDIAN:
> +		writel_be(val, (char *)afu->global_mmio_ptr + offset);
> +		break;
> +
> +	default:
> +		writel(val, (char *)afu->global_mmio_ptr + offset);
> +		break;
> +	}
> +
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(ocxl_global_mmio_write32);
> +
> +int ocxl_global_mmio_write64(struct ocxl_afu *afu, size_t offset,
> +				enum ocxl_endian endian, u64 val)
> +{
> +	if (offset > afu->config.global_mmio_size - 8)
> +		return -EINVAL;
> +
> +#ifdef __BIG_ENDIAN__
> +	if (endian == OCXL_HOST_ENDIAN)
> +		endian = OCXL_BIG_ENDIAN;
> +#endif
> +
> +	switch (endian) {
> +	case OCXL_BIG_ENDIAN:
> +		writeq_be(val, (char *)afu->global_mmio_ptr + offset);
> +		break;
> +
> +	default:
> +		writeq(val, (char *)afu->global_mmio_ptr + offset);
> +		break;
> +	}
> +
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(ocxl_global_mmio_write64);
> +
> +int ocxl_global_mmio_set32(struct ocxl_afu *afu, size_t offset,
> +				enum ocxl_endian endian, u32 mask)
> +{
> +	u32 tmp;
> +
> +	if (offset > afu->config.global_mmio_size - 4)
> +		return -EINVAL;
> +
> +#ifdef __BIG_ENDIAN__
> +	if (endian == OCXL_HOST_ENDIAN)
> +		endian = OCXL_BIG_ENDIAN;
> +#endif
> +
> +	switch (endian) {
> +	case OCXL_BIG_ENDIAN:
> +		tmp = readl_be((char *)afu->global_mmio_ptr + offset);
> +		tmp |= mask;
> +		writel_be(tmp, (char *)afu->global_mmio_ptr + offset);
> +		break;
> +
> +	default:
> +		tmp = readl((char *)afu->global_mmio_ptr + offset);
> +		tmp |= mask;
> +		writel(tmp, (char *)afu->global_mmio_ptr + offset);
> +		break;
> +	}
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(ocxl_global_mmio_set32);
> +
> +int ocxl_global_mmio_set64(struct ocxl_afu *afu, size_t offset,
> +				enum ocxl_endian endian, u64 mask)
> +{
> +	u64 tmp;
> +
> +	if (offset > afu->config.global_mmio_size - 8)
> +		return -EINVAL;
> +
> +#ifdef __BIG_ENDIAN__
> +	if (endian == OCXL_HOST_ENDIAN)
> +		endian = OCXL_BIG_ENDIAN;
> +#endif
> +
> +	switch (endian) {
> +	case OCXL_BIG_ENDIAN:
> +		tmp = readq_be((char *)afu->global_mmio_ptr + offset);
> +		tmp |= mask;
> +		writeq_be(tmp, (char *)afu->global_mmio_ptr + offset);
> +		break;
> +
> +	default:
> +		tmp = readq((char *)afu->global_mmio_ptr + offset);
> +		tmp |= mask;
> +		writeq(tmp, (char *)afu->global_mmio_ptr + offset);
> +		break;
> +	}
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(ocxl_global_mmio_set64);
> +
> +int ocxl_global_mmio_clear32(struct ocxl_afu *afu, size_t offset,
> +				enum ocxl_endian endian, u32 mask)
> +{
> +	u32 tmp;
> +
> +	if (offset > afu->config.global_mmio_size - 4)
> +		return -EINVAL;
> +
> +#ifdef __BIG_ENDIAN__
> +	if (endian == OCXL_HOST_ENDIAN)
> +		endian = OCXL_BIG_ENDIAN;
> +#endif
> +
> +	switch (endian) {
> +	case OCXL_BIG_ENDIAN:
> +		tmp = readl_be((char *)afu->global_mmio_ptr + offset);
> +		tmp &= ~mask;
> +		writel_be(tmp, (char *)afu->global_mmio_ptr + offset);
> +		break;
> +
> +	default:
> +		tmp = readl((char *)afu->global_mmio_ptr + offset);
> +		tmp &= ~mask;
> +		writel(tmp, (char *)afu->global_mmio_ptr + offset);
> +		break;
> +	}
> +
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(ocxl_global_mmio_clear32);
> +
> +int ocxl_global_mmio_clear64(struct ocxl_afu *afu, size_t offset,
> +				enum ocxl_endian endian, u64 mask)
> +{
> +	u64 tmp;
> +
> +	if (offset > afu->config.global_mmio_size - 8)
> +		return -EINVAL;
> +
> +#ifdef __BIG_ENDIAN__
> +	if (endian == OCXL_HOST_ENDIAN)
> +		endian = OCXL_BIG_ENDIAN;
> +#endif
> +
> +	switch (endian) {
> +	case OCXL_BIG_ENDIAN:
> +		tmp = readq_be((char *)afu->global_mmio_ptr + offset);
> +		tmp &= ~mask;
> +		writeq_be(tmp, (char *)afu->global_mmio_ptr + offset);
> +		break;
> +
> +	default:
> +		tmp = readq((char *)afu->global_mmio_ptr + offset);
> +		tmp &= ~mask;
> +		writeq(tmp, (char *)afu->global_mmio_ptr + offset);
> +		break;
> +	}
> +
> +	writeq(tmp, (char *)afu->global_mmio_ptr + offset);
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(ocxl_global_mmio_clear64);
> diff --git a/include/misc/ocxl.h b/include/misc/ocxl.h
> index 9530d3be1b30..3b320c39f0af 100644
> --- a/include/misc/ocxl.h
> +++ b/include/misc/ocxl.h
> @@ -49,6 +49,119 @@ struct ocxl_fn_config {
>   	s8 max_afu_index;
>   };
>   
> +// These are opaque outside the ocxl driver
> +struct ocxl_afu;
> +
> +enum ocxl_endian {
> +	OCXL_BIG_ENDIAN = 0,    /**< AFU data is big-endian */
> +	OCXL_LITTLE_ENDIAN = 1, /**< AFU data is little-endian */
> +	OCXL_HOST_ENDIAN = 2,   /**< AFU data is the same endianness as the host */
> +};
> +
> +/**
> + * Read a 32 bit value from global MMIO
> + *
> + * @afu: The AFU
> + * @offset: The Offset from the start of MMIO
> + * @endian: the endianness that the MMIO data is in
> + * @val: returns the value
> + *
> + * Returns 0 for success, negative on error
> + */
> +int ocxl_global_mmio_read32(struct ocxl_afu *afu, size_t offset,
> +				enum ocxl_endian endian, u32 *val);
> +
> +/**
> + * Read a 64 bit value from global MMIO
> + *
> + * @afu: The AFU
> + * @offset: The Offset from the start of MMIO
> + * @endian: the endianness that the MMIO data is in
> + * @val: returns the value
> + *
> + * Returns 0 for success, negative on error
> + */
> +int ocxl_global_mmio_read64(struct ocxl_afu *afu, size_t offset,
> +				enum ocxl_endian endian, u64 *val);
> +
> +/**
> + * Write a 32 bit value to global MMIO
> + *
> + * @afu: The AFU
> + * @offset: The Offset from the start of MMIO
> + * @endian: the endianness that the MMIO data is in
> + * @val: The value to write
> + *
> + * Returns 0 for success, negative on error
> + */
> +int ocxl_global_mmio_write32(struct ocxl_afu *afu, size_t offset,
> +				enum ocxl_endian endian, u32 val);
> +
> +/**
> + * Write a 64 bit value to global MMIO
> + *
> + * @afu: The AFU
> + * @offset: The Offset from the start of MMIO
> + * @endian: the endianness that the MMIO data is in
> + * @val: The value to write
> + *
> + * Returns 0 for success, negative on error
> + */
> +int ocxl_global_mmio_write64(struct ocxl_afu *afu, size_t offset,
> +				enum ocxl_endian endian, u64 val);
> +
> +/**
> + * Set bits in a 32 bit global MMIO register
> + *
> + * @afu: The AFU
> + * @offset: The Offset from the start of MMIO
> + * @endian: the endianness that the MMIO data is in
> + * @mask: a mask of the bits to set
> + *
> + * Returns 0 for success, negative on error
> + */
> +int ocxl_global_mmio_set32(struct ocxl_afu *afu, size_t offset,
> +				enum ocxl_endian endian, u32 mask);
> +
> +/**
> + * Set bits in a 64 bit global MMIO register
> + *
> + * @afu: The AFU
> + * @offset: The Offset from the start of MMIO
> + * @endian: the endianness that the MMIO data is in
> + * @mask: a mask of the bits to set
> + *
> + * Returns 0 for success, negative on error
> + */
> +int ocxl_global_mmio_set64(struct ocxl_afu *afu, size_t offset,
> +				enum ocxl_endian endian, u64 mask);
> +
> +/**
> + * Set bits in a 32 bit global MMIO register
> + *
> + * @afu: The AFU
> + * @offset: The Offset from the start of MMIO
> + * @endian: the endianness that the MMIO data is in
> + * @mask: a mask of the bits to set
> + *
> + * Returns 0 for success, negative on error
> + */
> +int ocxl_global_mmio_clear32(struct ocxl_afu *afu, size_t offset,
> +				enum ocxl_endian endian, u32 mask);
> +
> +/**
> + * Set bits in a 64 bit global MMIO register
> + *
> + * @afu: The AFU
> + * @offset: The Offset from the start of MMIO
> + * @endian: the endianness that the MMIO data is in
> + * @mask: a mask of the bits to set
> + *
> + * Returns 0 for success, negative on error
> + */
> +int ocxl_global_mmio_clear64(struct ocxl_afu *afu, size_t offset,
> +				enum ocxl_endian endian, u64 mask);
> +
>   /*
>    * Read the configuration space of a function and fill in a
>    * ocxl_fn_config structure with all the function details
> 

-- 
Andrew Donnellan              OzLabs, ADL Canberra
andrew.donnellan@au1.ibm.com  IBM Australia Limited