Re: [PATCH 1/3] ARM: mmp: add sram allocator

[Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>]

On 11:09 Mon 15 Aug     , Leo Yan wrote:
> On mmp platform, there have two sram banks:
> audio sram and internal sram. The audio sram is mainly for audio;
> the internal sram is for video, wtm and power management.
> So add the sram allocator using genalloc to manage them.
> 
> Every sram bank will register its own platform device
> info, after the sram allocator create the generic pool
> for the sram bank, the user module can use the pool's
> name to get the pool handler; then it can use the handler
> to alloc/free memory with genalloc APIs.
> 
> Signed-off-by: Leo Yan <leoy@marvell.com>
> ---
>  arch/arm/Kconfig                      |    1 +
>  arch/arm/mach-mmp/Makefile            |    2 +-
>  arch/arm/mach-mmp/include/mach/sram.h |   35 +++++++
>  arch/arm/mach-mmp/sram.c              |  168 +++++++++++++++++++++++++++++++++
>  4 files changed, 205 insertions(+), 1 deletions(-)
>  create mode 100644 arch/arm/mach-mmp/include/mach/sram.h
>  create mode 100644 arch/arm/mach-mmp/sram.c
> 
> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index 2c71a8f..c7545d1 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -559,6 +559,7 @@ config ARCH_MMP
>  	select TICK_ONESHOT
>  	select PLAT_PXA
>  	select SPARSE_IRQ
> +	select GENERIC_ALLOCATOR
>  	help
>  	  Support for Marvell's PXA168/PXA910(MMP) and MMP2 processor line.
>  
> diff --git a/arch/arm/mach-mmp/Makefile b/arch/arm/mach-mmp/Makefile
> index b0ac942..169c674 100644
> --- a/arch/arm/mach-mmp/Makefile
> +++ b/arch/arm/mach-mmp/Makefile
> @@ -7,7 +7,7 @@ obj-y				+= common.o clock.o devices.o time.o
>  # SoC support
>  obj-$(CONFIG_CPU_PXA168)	+= pxa168.o irq-pxa168.o
>  obj-$(CONFIG_CPU_PXA910)	+= pxa910.o irq-pxa168.o
> -obj-$(CONFIG_CPU_MMP2)		+= mmp2.o irq-mmp2.o
> +obj-$(CONFIG_CPU_MMP2)		+= mmp2.o irq-mmp2.o sram.o
>  
>  # board support
>  obj-$(CONFIG_MACH_ASPENITE)	+= aspenite.o
> diff --git a/arch/arm/mach-mmp/include/mach/sram.h b/arch/arm/mach-mmp/include/mach/sram.h
> new file mode 100644
> index 0000000..239e0fc
> --- /dev/null
> +++ b/arch/arm/mach-mmp/include/mach/sram.h
> @@ -0,0 +1,35 @@
> +/*
> + *  linux/arch/arm/mach-mmp/include/mach/sram.h
> + *
> + *  SRAM Memory Management
> + *
> + *  Copyright (c) 2011 Marvell Semiconductors Inc.
> + *
> + *  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.
> + *
> + */
> +
> +#ifndef __ASM_ARCH_SRAM_H
> +#define __ASM_ARCH_SRAM_H
> +
> +#include <linux/genalloc.h>
> +
> +/* ARBITRARY:  SRAM allocations are multiples of this 2^N size */
> +#define SRAM_GRANULARITY	512
> +
> +enum sram_type {
> +	MMP_SRAM_UNDEFINED = 0,
> +	MMP_ASRAM,
> +	MMP_ISRAM,
> +};
> +
> +struct sram_platdata {
> +	char *pool_name;
> +	int granularity;
> +};
> +
> +extern struct gen_pool *sram_get_gpool(char *pool_name);
> +
> +#endif /* __ASM_ARCH_SRAM_H */
> diff --git a/arch/arm/mach-mmp/sram.c b/arch/arm/mach-mmp/sram.c
> new file mode 100644
> index 0000000..4304f95
> --- /dev/null
> +++ b/arch/arm/mach-mmp/sram.c
> @@ -0,0 +1,168 @@
> +/*
> + *  linux/arch/arm/mach-mmp/sram.c
> + *
> + *  based on mach-davinci/sram.c - DaVinci simple SRAM allocator
> + *
> + *  Copyright (c) 2011 Marvell Semiconductors Inc.
> + *  All Rights Reserved
> + *
> + *  Add for mmp sram support - Leo Yan <leoy@marvell.com>
> + *
> + *  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/module.h>
> +#include <linux/init.h>
> +#include <linux/platform_device.h>
> +#include <linux/io.h>
> +#include <linux/err.h>
> +#include <linux/slab.h>
> +#include <linux/genalloc.h>
> +
> +#include <mach/sram.h>
> +
> +struct sram_bank_info {
> +	char *pool_name;
> +	struct gen_pool *gpool;
> +	int granularity;
> +
> +	phys_addr_t sram_phys;
> +	void __iomem *sram_virt;
> +	u32 sram_size;
> +
> +	struct list_head node;
> +};
> +
> +static DEFINE_MUTEX(sram_lock);
> +static LIST_HEAD(sram_bank_list);
> +
> +struct gen_pool *sram_get_gpool(char *pool_name)
> +{
> +	struct sram_bank_info *info = NULL;
> +
> +	if (!pool_name)
> +		return NULL;
> +
> +	mutex_lock(&sram_lock);
> +
> +	list_for_each_entry(info, &sram_bank_list, node)
> +		if (!strcmp(pool_name, info->pool_name))
> +			break;
> +
> +	mutex_unlock(&sram_lock);
> +
> +	if (&info->node == &sram_bank_list)
> +		return NULL;
> +
> +	return info->gpool;
> +}
> +EXPORT_SYMBOL(sram_get_gpool);
> +
> +static int __devinit sram_probe(struct platform_device *pdev)
> +{
> +	struct sram_platdata *pdata = pdev->dev.platform_data;
> +	struct sram_bank_info *info;
> +	struct resource *res;
> +	int ret = 0;
> +
> +	if (!pdata && !pdata->pool_name)
> +		return -ENODEV;
> +
> +	info = kzalloc(sizeof(*info), GFP_KERNEL);
> +	if (!info)
> +		return -ENOMEM;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (res == NULL) {
> +		dev_err(&pdev->dev, "no memory resource defined\n");
> +		ret = -ENODEV;
> +		goto out;
> +	}
> +
> +	if (!resource_size(res))
> +		return 0;
> +
> +	info->sram_phys   = (phys_addr_t)res->start;
> +	info->sram_size   = resource_size(res);
> +	info->sram_virt   = ioremap(info->sram_phys, info->sram_size);
> +	info->pool_name	  = kstrdup(pdata->pool_name, GFP_KERNEL);
> +	info->granularity = pdata->granularity;
if we want name pool this need to be managed at gen alloc level directly
not here

Best Regards,
J.