[PATCH v2 3/3] ARM: OMAP4+: Remove static iotable mappings for SRAM

Rajendra Nayak rnayak at ti.com
Thu Aug 29 09:56:43 EDT 2013


On Thursday 29 August 2013 06:53 PM, Santosh Shilimkar wrote:
> On Thursday 29 August 2013 07:23 AM, Rajendra Nayak wrote:
>> In order to handle errata I688, a page of sram was reserved by doing a
>> static iotable map. Now that we use gen_pool to manage sram, we can
>> completely remove all of these static mappings and use gen_pool_alloc()
>> to get the one page of sram space needed to implement errata I688.
>>
>> Suggested-by: Sekhar Nori <nsekhar at ti.com>
>> Signed-off-by: Rajendra Nayak <rnayak at ti.com>
>> ---
>>  Documentation/devicetree/bindings/arm/omap/mpu.txt |    5 ++++-
>>  arch/arm/boot/dts/omap4.dtsi                       |    1 +
>>  arch/arm/boot/dts/omap5.dtsi                       |    3 ++-
>>  arch/arm/mach-omap2/io.c                           |   17 -----------------
>>  arch/arm/mach-omap2/omap4-common.c                 |   17 ++++++++++++++++-
>>  arch/arm/mach-omap2/sram.c                         |    6 ------
>>  arch/arm/mach-omap2/sram.h                         |    6 ------
>>  7 files changed, 23 insertions(+), 32 deletions(-)
>>
> Add a note in the change-log about about omap_bus_sync() being NOP till the
> SRAM is initialized. Its not a problem since the idle loop hasn't
> started yet.

ok, will update the changelog, thanks.

> 
> Other than that looks fine.
>  
>> diff --git a/Documentation/devicetree/bindings/arm/omap/mpu.txt b/Documentation/devicetree/bindings/arm/omap/mpu.txt
>> index 1a5a42c..8915ba3 100644
>> --- a/Documentation/devicetree/bindings/arm/omap/mpu.txt
>> +++ b/Documentation/devicetree/bindings/arm/omap/mpu.txt
>> @@ -6,9 +6,12 @@ The MPU contain CPUs, GIC, L2 cache and a local PRCM.
>>  
>>  Required properties:
>>  - compatible : Should be "ti,omap3-mpu" for OMAP3
>> -               Should be "ti,omap4-mpu" for OMAP4
>> +               Should be "ti,omap4-mpu" for OMAP4 and OMAP5
>>  - ti,hwmods: "mpu"
>>  
>> +Optional properties:
>> +- sram:	Phandle to the ocmcram node
>> +
>>  Examples:
>>  
>>  - For an OMAP4 SMP system:
>> diff --git a/arch/arm/boot/dts/omap4.dtsi b/arch/arm/boot/dts/omap4.dtsi
>> index 1ba6a77..9114241 100644
>> --- a/arch/arm/boot/dts/omap4.dtsi
>> +++ b/arch/arm/boot/dts/omap4.dtsi
>> @@ -71,6 +71,7 @@
>>  		mpu {
>>  			compatible = "ti,omap4-mpu";
>>  			ti,hwmods = "mpu";
>> +			sram = <&ocmcram>;
>>  		};
>>  
>>  		dsp {
>> diff --git a/arch/arm/boot/dts/omap5.dtsi b/arch/arm/boot/dts/omap5.dtsi
>> index 461ffd8..e9b735b 100644
>> --- a/arch/arm/boot/dts/omap5.dtsi
>> +++ b/arch/arm/boot/dts/omap5.dtsi
>> @@ -72,8 +72,9 @@
>>  	soc {
>>  		compatible = "ti,omap-infra";
>>  		mpu {
>> -			compatible = "ti,omap5-mpu";
>> +			compatible = "ti,omap4-mpu";
>>  			ti,hwmods = "mpu";
>> +			sram = <&ocmcram>;
>>  		};
>>  	};
>>  
>> diff --git a/arch/arm/mach-omap2/io.c b/arch/arm/mach-omap2/io.c
>> index 4a3f06f..8b2334e 100644
>> --- a/arch/arm/mach-omap2/io.c
>> +++ b/arch/arm/mach-omap2/io.c
>> @@ -239,15 +239,6 @@ static struct map_desc omap44xx_io_desc[] __initdata = {
>>  		.length		= L4_PER_44XX_SIZE,
>>  		.type		= MT_DEVICE,
>>  	},
>> -#ifdef CONFIG_OMAP4_ERRATA_I688
>> -	{
>> -		.virtual	= OMAP4_SRAM_VA,
>> -		.pfn		= __phys_to_pfn(OMAP4_SRAM_PA),
>> -		.length		= PAGE_SIZE,
>> -		.type		= MT_MEMORY_SO,
>> -	},
>> -#endif
>> -
>>  };
>>  #endif
>>  
>> @@ -277,14 +268,6 @@ static struct map_desc omap54xx_io_desc[] __initdata = {
>>  		.length		= L4_PER_54XX_SIZE,
>>  		.type		= MT_DEVICE,
>>  	},
>> -#ifdef CONFIG_OMAP4_ERRATA_I688
>> -	{
>> -		.virtual	= OMAP4_SRAM_VA,
>> -		.pfn		= __phys_to_pfn(OMAP4_SRAM_PA),
>> -		.length		= PAGE_SIZE,
>> -		.type		= MT_MEMORY_SO,
>> -	},
>> -#endif
>>  };
>>  #endif
>>  
>> diff --git a/arch/arm/mach-omap2/omap4-common.c b/arch/arm/mach-omap2/omap4-common.c
>> index 5791143..6b5ffb3 100644
>> --- a/arch/arm/mach-omap2/omap4-common.c
>> +++ b/arch/arm/mach-omap2/omap4-common.c
>> @@ -24,6 +24,7 @@
>>  #include <linux/irqchip/arm-gic.h>
>>  #include <linux/of_address.h>
>>  #include <linux/reboot.h>
>> +#include <linux/genalloc.h>
>>  
>>  #include <asm/hardware/cache-l2x0.h>
>>  #include <asm/mach/map.h>
>> @@ -71,6 +72,21 @@ void omap_bus_sync(void)
>>  }
>>  EXPORT_SYMBOL(omap_bus_sync);
>>  
>> +static int __init omap4_sram_init(void)
>> +{
>> +	struct device_node *np;
>> +	struct gen_pool *sram_pool;
>> +
>> +	np = of_find_compatible_node(NULL, NULL, "ti,omap4-mpu");
>> +	if (!np)
>> +		pr_warn("%s:Unable to allocate sram needed to handle errata I688\n",
>> +			 __func__);
>> +	sram_pool = of_get_named_gen_pool(np, "sram", 0);
>> +	sram_sync = (void *)gen_pool_alloc(sram_pool, PAGE_SIZE);
>> +	return 0;
>> +}
>> +omap_arch_initcall(omap4_sram_init);
>> +
>>  /* Steal one page physical memory for barrier implementation */
>>  int __init omap_barrier_reserve_memblock(void)
>>  {
>> @@ -91,7 +107,6 @@ void __init omap_barriers_init(void)
>>  	dram_io_desc[0].type = MT_MEMORY_SO;
>>  	iotable_init(dram_io_desc, ARRAY_SIZE(dram_io_desc));
>>  	dram_sync = (void __iomem *) dram_io_desc[0].virtual;
>> -	sram_sync = (void __iomem *) OMAP4_SRAM_VA;
>>  
>>  	pr_info("OMAP4: Map 0x%08llx to 0x%08lx for dram barrier\n",
>>  		(long long) paddr, dram_io_desc[0].virtual);
>> diff --git a/arch/arm/mach-omap2/sram.c b/arch/arm/mach-omap2/sram.c
>> index d5ecb75..8591044 100644
>> --- a/arch/arm/mach-omap2/sram.c
>> +++ b/arch/arm/mach-omap2/sram.c
>> @@ -124,12 +124,6 @@ static void __init omap2_map_sram(void)
>>  {
>>  	int cached = 1;
>>  
>> -#ifdef CONFIG_OMAP4_ERRATA_I688
>> -	if (cpu_is_omap44xx()) {
>> -		omap_sram_start += PAGE_SIZE;
>> -		omap_sram_size -= SZ_16K;
>> -	}
>> -#endif
>>  	if (cpu_is_omap34xx()) {
>>  		/*
>>  		 * SRAM must be marked as non-cached on OMAP3 since the
>> diff --git a/arch/arm/mach-omap2/sram.h b/arch/arm/mach-omap2/sram.h
>> index 3f83b80..948d3ed 100644
>> --- a/arch/arm/mach-omap2/sram.h
>> +++ b/arch/arm/mach-omap2/sram.h
>> @@ -74,9 +74,3 @@ static inline void omap_push_sram_idle(void) {}
>>   */
>>  #define OMAP2_SRAM_PA		0x40200000
>>  #define OMAP3_SRAM_PA           0x40200000
>> -#ifdef CONFIG_OMAP4_ERRATA_I688
>> -#define OMAP4_SRAM_PA		0x40304000
>> -#define OMAP4_SRAM_VA		0xfe404000
>> -#else
>> -#define OMAP4_SRAM_PA		0x40300000
>> -#endif
>>
> 




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