Subject: [PATCH v4 1/2] memory: ti-aemif: introduce AEMIF driver

From: [email-masked] (Greg KH)
Date: Tue, 18 Feb 2014 12:30:49 -0800

On Wed, Feb 05, 2014 at 09:46:13PM +0200, Ivan Khoronzhuk wrote:
> Add new AEMIF driver for EMIF16 Texas Instruments controller.
> The EMIF16 module is intended to provide a glue-less interface to
> a variety of asynchronous memory devices like ASRA M, NOR and NAND
> memory. A total of 256M bytes of any of these memories can be
> accessed at any given time via 4 chip selects with 64M byte access
> per chip select.
> 
> Synchronous memories such as DDR1 SD RAM, SDR SDRAM and Mobile SDR
> are not supported.
> 
> This controller is used on SoCs like Davinci, Keysone2
> 
> Acked-by: Santosh Shilimkar <[email-masked]
> Signed-off-by: [initial author] Murali Karicheri <[email-masked]>

What's this [] stuff?

If Murali wrote this, that name needs to be in a "From:" line in the
patch to properly attribute it, and drop the [] here.

> Signed-off-by: Ivan Khoronzhuk <[email-masked]>
> ---
>  drivers/memory/Kconfig    |  11 ++
>  drivers/memory/Makefile   |   1 +
>  drivers/memory/ti-aemif.c | 429 ++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 441 insertions(+)
>  create mode 100644 drivers/memory/ti-aemif.c
> 
> diff --git a/drivers/memory/Kconfig b/drivers/memory/Kconfig
> index 29a11db..7bc3982 100644
> --- a/drivers/memory/Kconfig
> +++ b/drivers/memory/Kconfig
> @@ -7,6 +7,17 @@ menuconfig MEMORY
>  
>  if MEMORY
>  
> +config TI_AEMIF
> +	tristate "Texas Instruments AEMIF driver"
> +	depends on (ARCH_DAVINCI || ARCH_KEYSTONE) && OF
> +	help
> +	  This driver is for the AEMIF module available in Texas Instruments
> +	  SoCs. AEMIF stands for Asynchronous External Memory Interface and
> +	  is intended to provide a glue-less interface to a variety of
> +	  asynchronuous memory devices like ASRAM, NOR and NAND memory. A total
> +	  of 256M bytes of any of these memories can be accessed at a given
> +	  time via four chip selects with 64M byte access per chip select.
> +
>  config TI_EMIF
>  	tristate "Texas Instruments EMIF driver"
>  	depends on ARCH_OMAP2PLUS
> diff --git a/drivers/memory/Makefile b/drivers/memory/Makefile
> index 969d923..d4e150c 100644
> --- a/drivers/memory/Makefile
> +++ b/drivers/memory/Makefile
> @@ -5,6 +5,7 @@
>  ifeq ($(CONFIG_DDR),y)
>  obj-$(CONFIG_OF)		+= of_memory.o
>  endif
> +obj-$(CONFIG_TI_AEMIF)		+= ti-aemif.o
>  obj-$(CONFIG_TI_EMIF)		+= emif.o
>  obj-$(CONFIG_MVEBU_DEVBUS)	+= mvebu-devbus.o
>  obj-$(CONFIG_TEGRA20_MC)	+= tegra20-mc.o
> diff --git a/drivers/memory/ti-aemif.c b/drivers/memory/ti-aemif.c
> new file mode 100644
> index 0000000..8d15d87
> --- /dev/null
> +++ b/drivers/memory/ti-aemif.c
> @@ -0,0 +1,429 @@
> +/*
> + * TI AEMIF driver
> + *
> + * Copyright (C) 2010 - 2013 Texas Instruments Incorporated. http://www.ti.com/
> + *
> + * Authors:
> + * Murali Karicheri <[email-masked]>
> + * Ivan Khoronzhuk <[email-masked]>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/err.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_platform.h>
> +#include <linux/platform_device.h>
> +
> +#define TA_SHIFT	2
> +#define RHOLD_SHIFT	4
> +#define RSTROBE_SHIFT	7
> +#define RSETUP_SHIFT	13
> +#define WHOLD_SHIFT	17
> +#define WSTROBE_SHIFT	20
> +#define WSETUP_SHIFT	26
> +#define EW_SHIFT	30
> +#define SS_SHIFT	31
> +
> +#define TA(x)		((x) << TA_SHIFT)
> +#define RHOLD(x)	((x) << RHOLD_SHIFT)
> +#define RSTROBE(x)	((x) << RSTROBE_SHIFT)
> +#define RSETUP(x)	((x) << RSETUP_SHIFT)
> +#define WHOLD(x)	((x) << WHOLD_SHIFT)
> +#define WSTROBE(x)	((x) << WSTROBE_SHIFT)
> +#define WSETUP(x)	((x) << WSETUP_SHIFT)
> +#define EW(x)		((x) << EW_SHIFT)
> +#define SS(x)		((x) << SS_SHIFT)
> +
> +#define ASIZE_MAX	0x1
> +#define TA_MAX		0x3
> +#define RHOLD_MAX	0x7
> +#define RSTROBE_MAX	0x3f
> +#define RSETUP_MAX	0xf
> +#define WHOLD_MAX	0x7
> +#define WSTROBE_MAX	0x3f
> +#define WSETUP_MAX	0xf
> +#define EW_MAX		0x1
> +#define SS_MAX		0x1
> +#define NUM_CS		4
> +
> +#define TA_VAL(x)	(((x) & TA(TA_MAX)) >> TA_SHIFT)
> +#define RHOLD_VAL(x)	(((x) & RHOLD(RHOLD_MAX)) >> RHOLD_SHIFT)
> +#define RSTROBE_VAL(x)	(((x) & RSTROBE(RSTROBE_MAX)) >> RSTROBE_SHIFT)
> +#define RSETUP_VAL(x)	(((x) & RSETUP(RSETUP_MAX)) >> RSETUP_SHIFT)
> +#define WHOLD_VAL(x)	(((x) & WHOLD(WHOLD_MAX)) >> WHOLD_SHIFT)
> +#define WSTROBE_VAL(x)	(((x) & WSTROBE(WSTROBE_MAX)) >> WSTROBE_SHIFT)
> +#define WSETUP_VAL(x)	(((x) & WSETUP(WSETUP_MAX)) >> WSETUP_SHIFT)
> +#define EW_VAL(x)	(((x) & EW(EW_MAX)) >> EW_SHIFT)
> +#define SS_VAL(x)	(((x) & SS(SS_MAX)) >> SS_SHIFT)
> +
> +#define NRCSR_OFFSET	0x00
> +#define AWCCR_OFFSET	0x04
> +#define A1CR_OFFSET	0x10
> +
> +#define ACR_ASIZE_MASK	0x3
> +#define ACR_EW_MASK	BIT(30)
> +#define ACR_SS_MASK	BIT(31)
> +#define ASIZE_16BIT	1
> +
> +#define CONFIG_MASK	(TA(TA_MAX) | \
> +				RHOLD(RHOLD_MAX) | \
> +				RSTROBE(RSTROBE_MAX) |	\
> +				RSETUP(RSETUP_MAX) | \
> +				WHOLD(WHOLD_MAX) | \
> +				WSTROBE(WSTROBE_MAX) | \
> +				WSETUP(WSETUP_MAX) | \
> +				EW(EW_MAX) | SS(SS_MAX) | \
> +				ASIZE_MAX)
> +
> +#define DRV_NAME	"ti-aemif"

What's wrong with KBUILD_MODNAME?

> +static int aemif_probe(struct platform_device *pdev)
> +{
> +	int ret  = -ENODEV, i;

Extra spaces?

Split this into two lines?

> +	struct resource *res;
> +	struct device *dev = &pdev->dev;
> +	struct device_node *np = dev->of_node;
> +	struct device_node *child_np;
> +	struct aemif_device *aemif;
> +
> +	if (np == NULL)
> +		return 0;
> +
> +	aemif = devm_kzalloc(dev, sizeof(*aemif), GFP_KERNEL);
> +	if (!aemif) {
> +		dev_err(dev, "cannot allocate memory for aemif\n");

Not needed, you'll get a message from kzalloc about this.

> +		return -ENOMEM;
> +	}
> +
> +	platform_set_drvdata(pdev, aemif);
> +
> +	aemif->clk = devm_clk_get(dev, NULL);
> +	if (IS_ERR(aemif->clk)) {
> +		dev_err(dev, "cannot get clock 'aemif'\n");
> +		return PTR_ERR(aemif->clk);

No freeing memory?

> +	}
> +
> +	clk_prepare_enable(aemif->clk);
> +	aemif->clk_rate = clk_get_rate(aemif->clk) / MSEC_PER_SEC;
> +
> +	if (of_device_is_compatible(np, "ti,da850-aemif"))
> +		aemif->cs_offset = 2;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	aemif->base = devm_ioremap_resource(dev, res);
> +	if (IS_ERR(aemif->base)) {
> +		ret = PTR_ERR(aemif->base);
> +		goto error;
> +	}
> +
> +	/*
> +	 * For every controller device node, there is a cs device node that
> +	 * describe the bus configuration parameters. This functions iterate
> +	 * over these nodes and update the cs data array.
> +	 */
> +	for_each_available_child_of_node(np, child_np) {
> +		ret = of_aemif_parse_abus_config(pdev, child_np);
> +		if (ret < 0)
> +			goto error;
> +	}
> +
> +	for (i = 0; i < aemif->num_cs; i++) {
> +		ret = aemif_config_abus(pdev, i);
> +		if (ret < 0) {
> +			dev_err(dev, "Error configuring chip select %d\n",
> +				aemif->cs_data[i].cs);
> +			goto error;
> +		}
> +	}
> +
> +	/*
> +	 * Create a child devices explicitly from here to
> +	 * guarantee that the child will be probed after the AEMIF timing
> +	 * parameters are set.
> +	 */
> +	for_each_available_child_of_node(np, child_np) {
> +		ret = of_platform_populate(child_np, NULL, NULL, dev);
> +		if (ret < 0)
> +			goto error;
> +	}
> +
> +	return 0;
> +error:
> +	clk_disable_unprepare(aemif->clk);
> +	return ret;

No freeing memory?

> +}
> +
> +static int aemif_remove(struct platform_device *pdev)
> +{
> +	struct aemif_device *aemif = platform_get_drvdata(pdev);
> +	clk_disable_unprepare(aemif->clk);

Extra line needed.

> +	return 0;
> +}

thanks,

greg k-h