lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <alpine.DEB.2.20.1706270800240.8058@mgerlach-VirtualBox>
Date:   Tue, 27 Jun 2017 08:15:48 -0700 (PDT)
From:   matthew.gerlach@...ux.intel.com
To:     Marek Vasut <marek.vasut@...il.com>
cc:     vndao@...era.com, dwmw2@...radead.org, computersforpeace@...il.com,
        boris.brezillon@...e-electrons.com, richard@....at,
        cyrille.pitchen@...ev4u.fr, robh+dt@...nel.org,
        mark.rutland@....com, linux-mtd@...ts.infradead.org,
        devicetree@...r.kernel.org, linux-kernel@...r.kernel.org,
        gregkh@...uxfoundation.org, davem@...emloft.net, mchehab@...nel.org
Subject: Re: [PATCH 3/3] mtd: spi-nor: Altera Quadspi Flash Controller v2
 Platform driver



On Tue, 27 Jun 2017, Marek Vasut wrote:

> On 06/26/2017 06:13 PM, matthew.gerlach@...ux.intel.com wrote:
>> From: Matthew Gerlach <matthew.gerlach@...ux.intel.com>
>
> Just wrap it into the Altera QSPI driver , no need for separate platform
> driver IMO.

Hi Marek,

I answered this question when you asked why the header file was necessary, 
but I think further discussion could be helpful, since this problem is 
becoming more prevelent.  The Altera Quadspi component is a soft IP in a
FPGA, and the processor using the component may or may not have device 
tree support compiled into the Linux kernel.  Since device tree support 
may or may not be available, the device tree specific code must be separated
from the core driver code.

One can certainly make the case, that device tree support could/should
be available everywhere, but the current reality is most x86 Linux
kernel configurations do not include device tree support.

For the record, I believe device trees, and more specifically device tree 
overlays, are the best way for Linux to use FPGAs, but I have to deal with 
the current realities.

Thanks again for all the great feedback.

Matthew Gerlach

>
>> Signed-off-by: Matthew Gerlach <matthew.gerlach@...ux.intel.com>
>> ---
>>  MAINTAINERS                                   |   1 +
>>  drivers/mtd/spi-nor/Kconfig                   |   5 +
>>  drivers/mtd/spi-nor/Makefile                  |   1 +
>>  drivers/mtd/spi-nor/altera-quadspi-platform.c | 137 ++++++++++++++++++++++++++
>>  4 files changed, 144 insertions(+)
>>  create mode 100644 drivers/mtd/spi-nor/altera-quadspi-platform.c
>>
>> diff --git a/MAINTAINERS b/MAINTAINERS
>> index ae33fa6..c32bb98 100644
>> --- a/MAINTAINERS
>> +++ b/MAINTAINERS
>> @@ -653,6 +653,7 @@ M:	Matthew Gerlach <matthew.gerlach@...ux.intel.com>
>>  L:	linux-mtd@...ts.infradead.org
>>  S:	Maintained
>>  F:	drivers/mtd/spi-nor/altera-quadspi.c
>> +F:	drivers/mtd/spi-nor/altera-quadspi-platform.c
>>  F:	inclulde/linux/mtd/altera-quadspi.h
>>
>>  ALTERA SYSTEM RESOURCE DRIVER FOR ARRIA10 DEVKIT
>> diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig
>> index 89fe425..f3d5c01 100644
>> --- a/drivers/mtd/spi-nor/Kconfig
>> +++ b/drivers/mtd/spi-nor/Kconfig
>> @@ -118,4 +118,9 @@ config SPI_ALTERA_QUADSPI
>>          help
>>            Enable support for version 2 of Altera Quad SPI Flash Controller.
>>
>> +config SPI_ALTERA_QUADSPI_PLATFORM
>> +	tristate "Platform support for Altera Quad SPI Flash Controller II"
>> +	help
>> +	  Platform driver support for  Altera Quad SPI Flash Controller II"
>> +
>>  endif # MTD_SPI_NOR
>> diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile
>> index 024c6ac..042f87e 100644
>> --- a/drivers/mtd/spi-nor/Makefile
>> +++ b/drivers/mtd/spi-nor/Makefile
>> @@ -10,4 +10,5 @@ obj-$(CONFIG_SPI_INTEL_SPI)	+= intel-spi.o
>>  obj-$(CONFIG_SPI_INTEL_SPI_PLATFORM)	+= intel-spi-platform.o
>>  obj-$(CONFIG_SPI_STM32_QUADSPI)	+= stm32-quadspi.o
>>  obj-$(CONFIG_SPI_ALTERA_QUADSPI) += altera-quadspi.o
>> +obj-$(CONFIG_SPI_ALTERA_QUADSPI_PLATFORM) += altera-quadspi-platform.o
>>
>> diff --git a/drivers/mtd/spi-nor/altera-quadspi-platform.c b/drivers/mtd/spi-nor/altera-quadspi-platform.c
>> new file mode 100644
>> index 0000000..c8d2a47
>> --- /dev/null
>> +++ b/drivers/mtd/spi-nor/altera-quadspi-platform.c
>> @@ -0,0 +1,137 @@
>> +/*
>> + * Copyright (C) 2014 Altera Corporation. All rights reserved.
>> + * Copyright (C) 2017 Intel Corporation. All rights reserved.
>> + *
>> + * This program is free software; you can redistribute it and/or modify it
>> + * under the terms and conditions of the GNU General Public License,
>> + * version 2, as published by the Free Software Foundation.
>> + *
>> + * This program is distributed in the hope it will be useful, but WITHOUT
>> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
>> + * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
>> + * more details.
>> + *
>> + * You should have received a copy of the GNU General Public License along with
>> + * this program.  If not, see <http://www.gnu.org/licenses/>.
>> + */
>> +
>> +#include <linux/module.h>
>> +#include <linux/mtd/altera-quadspi.h>
>> +#include <linux/of.h>
>> +#include <linux/of_address.h>
>> +#include <linux/of_device.h>
>> +
>> +static int altera_quadspi_probe(struct platform_device *pdev)
>> +{
>> +	struct device_node *np = pdev->dev.of_node;
>> +	struct device *dev = &pdev->dev;
>> +	struct resource *res;
>> +	void __iomem *csr_base;
>> +	void __iomem *data_base;
>> +	void __iomem *window_base = NULL;
>> +	u32 window_size = 0;
>> +	u32 flags = 0;
>> +	u32 bank;
>> +	int ret;
>> +	struct device_node *pp;
>> +
>> +	if (!np) {
>> +		dev_err(dev, "no device found\n");
>> +		return -ENODEV;
>> +	}
>> +
>> +	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "avl_csr");
>> +	csr_base = devm_ioremap_resource(dev, res);
>> +	if (IS_ERR(csr_base)) {
>> +		dev_err(dev, "%s: ERROR: failed to map csr base\n", __func__);
>> +		return PTR_ERR(csr_base);
>> +	}
>> +
>> +	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "avl_mem");
>> +	data_base = devm_ioremap_resource(&pdev->dev, res);
>> +	if (IS_ERR(data_base)) {
>> +		dev_err(dev, "%s: ERROR: failed to map data base\n", __func__);
>> +		return PTR_ERR(data_base);
>> +	}
>> +
>> +	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "avl_window");
>> +	if (res) {
>> +		window_base = NULL;
>> +		window_base = devm_ioremap_resource(dev, res);
>> +		if (IS_ERR(window_base)) {
>> +			dev_err(dev, "%s: ERROR: failed to map window base\n",
>> +				__func__);
>> +			return PTR_ERR(data_base);
>> +		}
>> +
>> +		of_property_read_u32(dev->of_node, "window-size", &window_size);
>> +
>> +		if (!window_size) {
>> +			dev_err(dev,
>> +				"alv_window defined, %s",
>> +				"but no window-size defined\n");
>> +			return -EINVAL;
>> +		}
>> +	}
>> +
>> +	if (of_property_read_bool(np, "read-bit-reverse"))
>> +		flags |= ALTERA_QUADSPI_FL_BITREV_READ;
>> +
>> +	if (of_property_read_bool(np, "write-bit-reverse"))
>> +		flags |= ALTERA_QUADSPI_FL_BITREV_WRITE;
>> +
>> +	ret = altera_quadspi_create(dev, csr_base, data_base,
>> +				    window_base, (size_t)window_size, flags);
>> +
>> +	if (ret) {
>> +		dev_err(dev, "failed to create qspi device\n");
>> +		return ret;
>> +	}
>> +
>> +	for_each_available_child_of_node(np, pp) {
>> +		of_property_read_u32(pp, "reg", &bank);
>> +		if (bank >= ALTERA_QUADSPI_MAX_NUM_FLASH_CHIP) {
>> +			dev_err(dev, "bad reg value %u >= %u\n", bank,
>> +				ALTERA_QUADSPI_MAX_NUM_FLASH_CHIP);
>> +			goto error;
>> +		}
>> +
>> +		if (altera_qspi_add_bank(dev, bank, pp)) {
>> +			dev_err(dev, "failed to add bank %u\n", bank);
>> +			goto error;
>> +		}
>> +	}
>> +
>> +	return 0;
>> +error:
>> +	altera_quadspi_remove_banks(dev);
>> +	return -EIO;
>> +}
>> +
>> +static int altera_quadspi_remove(struct platform_device *pdev)
>> +{
>> +	return altera_quadspi_remove_banks(&pdev->dev);
>> +}
>> +
>> +static const struct of_device_id altera_quadspi_id_table[] = {
>> +
>> +	{ .compatible = "altr,quadspi-v2",},
>> +	{}
>> +};
>> +MODULE_DEVICE_TABLE(of, altera_quadspi_id_table);
>> +
>> +static struct platform_driver altera_quadspi_driver = {
>> +	.driver = {
>> +		.name = "altera_quadspi_platform",
>> +		.of_match_table = altera_quadspi_id_table,
>> +	},
>> +	.probe = altera_quadspi_probe,
>> +	.remove = altera_quadspi_remove,
>> +};
>> +module_platform_driver(altera_quadspi_driver);
>> +
>> +MODULE_AUTHOR("Viet Nga Dao <vndao@...era.com>");
>> +MODULE_AUTHOR("Yong Sern Lau <lau.yong.sern@...el.com>");
>> +MODULE_AUTHOR("Matthew Gerlach <matthew.gerlach@...ux.intel.com>");
>> +MODULE_DESCRIPTION("Altera QuadSPI Version 2 Platform Driver");
>> +MODULE_LICENSE("GPL v2");
>>
>
>
> -- 
> Best regards,
> Marek Vasut
>

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ