[U-Boot] [PATCH 4/5] sunxi: let sunxi_dram_init return unsigned long long

Icenowy Zheng icenowy at aosc.io
Thu Feb 8 06:56:01 UTC 2018


在 2018-02-08 08:37,André Przywara 写道:
> On 07/02/18 19:35, Icenowy Zheng wrote:
> 
> Hi,
> 
>> As 4GiB capacity is above the range of 32-bit unsigned integer, raise
>> the return type of sunxi_dram_init() to unsigned long long, thus it 
>> can
>> hold 4GiB capacity (or maybe more on A80).
>> Some controllers that are possible to use 4GiB+ memory module are
>> also changed to calculate its memory capacity in unsigned long long.
>> 
>> Signed-off-by: Icenowy Zheng <icenowy at aosc.io>
>> ---
>>  arch/arm/include/asm/arch-sunxi/dram.h | 2 +-
>>  arch/arm/mach-sunxi/dram_sun6i.c       | 2 +-
>>  arch/arm/mach-sunxi/dram_sun8i_a23.c   | 2 +-
>>  arch/arm/mach-sunxi/dram_sun8i_a33.c   | 2 +-
>>  arch/arm/mach-sunxi/dram_sun8i_a83t.c  | 2 +-
>>  arch/arm/mach-sunxi/dram_sun9i.c       | 4 ++--
>>  arch/arm/mach-sunxi/dram_sunxi_dw.c    | 4 ++--
>>  board/sunxi/board.c                    | 2 +-
>>  board/sunxi/dram_sun4i_auto.c          | 2 +-
>>  board/sunxi/dram_sun5i_auto.c          | 2 +-
>>  10 files changed, 12 insertions(+), 12 deletions(-)
>> 
>> diff --git a/arch/arm/include/asm/arch-sunxi/dram.h 
>> b/arch/arm/include/asm/arch-sunxi/dram.h
>> index 80abac95b8..d08b82371d 100644
>> --- a/arch/arm/include/asm/arch-sunxi/dram.h
>> +++ b/arch/arm/include/asm/arch-sunxi/dram.h
>> @@ -32,7 +32,7 @@
>>  #include <asm/arch/dram_sun4i.h>
>>  #endif
>> 
>> -unsigned long sunxi_dram_init(void);
>> +unsigned long long sunxi_dram_init(void);
> 
> Since this is explicitly about > 4GB/32 bits, I would suggest we just
> use uint64_t here, instead of guessing what long long means.

Seems OK. But is there any sure suffix for uint64_t? For unsigned long
long we can use ULL.

> 
> But can't we just change the semantics of sunxi_dram_init() to return
> megabytes instead? sun9i already uses this internally, and just blows 
> it
> up in the wrapper. I don't think we have anything with a granularity
> smaller than 1MB?
> Then we could just leave it at native bit size, and spare poor ARMv7
> from struggling with 64 bit arithmetic.

The calculated size is just in byte.

The A80 code first shifted it to MiB in DRAMC_get_dram_size() and then
shifted it back to B in sunxi_dram_init(); however the code that shifts
it to MiB only applies to drivers which have shift operation.

The other target driver, dram_sunxi_dw, uses both bit shifts and 
multiply
when calculating the size, and to have 4096MiB value we still need to
calculate the byte value as uint64_t and then shift it to MiB value.
(The multiply value can get as high as 4096, so it's highly possible
that the shift value could be less than 20.)

I think keeping the return value as byte will make the code more clear.

> 
> Cheers,
> Andre.
> 
>>  void mctl_await_completion(u32 *reg, u32 mask, u32 val);
>>  bool mctl_mem_matches(u32 offset);
>> 
>> diff --git a/arch/arm/mach-sunxi/dram_sun6i.c 
>> b/arch/arm/mach-sunxi/dram_sun6i.c
>> index 5dbbf6186f..bdf52a2c38 100644
>> --- a/arch/arm/mach-sunxi/dram_sun6i.c
>> +++ b/arch/arm/mach-sunxi/dram_sun6i.c
>> @@ -326,7 +326,7 @@ static void mctl_port_cfg(void)
>>  	writel(0x00000307, &mctl_com->mbagcr[5]);
>>  }
>> 
>> -unsigned long sunxi_dram_init(void)
>> +unsigned long long sunxi_dram_init(void)
>>  {
>>  	struct sunxi_mctl_com_reg * const mctl_com =
>>  		(struct sunxi_mctl_com_reg *)SUNXI_DRAM_COM_BASE;
>> diff --git a/arch/arm/mach-sunxi/dram_sun8i_a23.c 
>> b/arch/arm/mach-sunxi/dram_sun8i_a23.c
>> index c53671a0e9..169ccff41a 100644
>> --- a/arch/arm/mach-sunxi/dram_sun8i_a23.c
>> +++ b/arch/arm/mach-sunxi/dram_sun8i_a23.c
>> @@ -264,7 +264,7 @@ static void mctl_init(u32 *bus_width)
>>  	writel(0x00000000, &mctl_ctl->rfshctl3);
>>  }
>> 
>> -unsigned long sunxi_dram_init(void)
>> +unsigned long long sunxi_dram_init(void)
>>  {
>>  	struct sunxi_mctl_com_reg * const mctl_com =
>>  		(struct sunxi_mctl_com_reg *)SUNXI_DRAM_COM_BASE;
>> diff --git a/arch/arm/mach-sunxi/dram_sun8i_a33.c 
>> b/arch/arm/mach-sunxi/dram_sun8i_a33.c
>> index fa1620cb39..dfbbe6f39c 100644
>> --- a/arch/arm/mach-sunxi/dram_sun8i_a33.c
>> +++ b/arch/arm/mach-sunxi/dram_sun8i_a33.c
>> @@ -325,7 +325,7 @@ static void mctl_sys_init(struct dram_para *para)
>>  	udelay(250);
>>  }
>> 
>> -unsigned long sunxi_dram_init(void)
>> +unsigned long long sunxi_dram_init(void)
>>  {
>>  	struct sunxi_mctl_com_reg * const mctl_com =
>>  			(struct sunxi_mctl_com_reg *)SUNXI_DRAM_COM_BASE;
>> diff --git a/arch/arm/mach-sunxi/dram_sun8i_a83t.c 
>> b/arch/arm/mach-sunxi/dram_sun8i_a83t.c
>> index 55df1b9d54..ec4bccd635 100644
>> --- a/arch/arm/mach-sunxi/dram_sun8i_a83t.c
>> +++ b/arch/arm/mach-sunxi/dram_sun8i_a83t.c
>> @@ -423,7 +423,7 @@ static void mctl_sys_init(struct dram_para *para)
>>  	udelay(250);
>>  }
>> 
>> -unsigned long sunxi_dram_init(void)
>> +unsigned long long sunxi_dram_init(void)
>>  {
>>  	struct sunxi_mctl_com_reg * const mctl_com =
>>  			(struct sunxi_mctl_com_reg *)SUNXI_DRAM_COM_BASE;
>> diff --git a/arch/arm/mach-sunxi/dram_sun9i.c 
>> b/arch/arm/mach-sunxi/dram_sun9i.c
>> index 8c681f3541..dcb20f763e 100644
>> --- a/arch/arm/mach-sunxi/dram_sun9i.c
>> +++ b/arch/arm/mach-sunxi/dram_sun9i.c
>> @@ -854,7 +854,7 @@ signed int DRAMC_get_dram_size(void)
>>  	return 1 << dram_size;
>>  }
>> 
>> -unsigned long sunxi_dram_init(void)
>> +unsigned long long sunxi_dram_init(void)
>>  {
>>  	struct sunxi_mctl_com_reg * const mctl_com =
>>  		(struct sunxi_mctl_com_reg *)SUNXI_DRAM_COM_BASE;
>> @@ -957,5 +957,5 @@ unsigned long sunxi_dram_init(void)
>>  	mctl_com_init(&para);
>> 
>>  	/* return the proper RAM size */
>> -	return DRAMC_get_dram_size() << 20;
>> +	return ((unsigned long long)DRAMC_get_dram_size()) << 20;
>>  }
>> diff --git a/arch/arm/mach-sunxi/dram_sunxi_dw.c 
>> b/arch/arm/mach-sunxi/dram_sunxi_dw.c
>> index 78b4ffb9c3..3bff1c46cd 100644
>> --- a/arch/arm/mach-sunxi/dram_sunxi_dw.c
>> +++ b/arch/arm/mach-sunxi/dram_sunxi_dw.c
>> @@ -682,7 +682,7 @@ static void mctl_auto_detect_dram_size(uint16_t 
>> socid, struct dram_para *para)
>>  	   3,  3,  3,  3,  3,  3,  3,  3,			\
>>  	   3,  3,  3,  3,  2,  0,  0      }
>> 
>> -unsigned long sunxi_dram_init(void)
>> +unsigned long long sunxi_dram_init(void)
>>  {
>>  	struct sunxi_mctl_com_reg * const mctl_com =
>>  			(struct sunxi_mctl_com_reg *)SUNXI_DRAM_COM_BASE;
>> @@ -763,6 +763,6 @@ unsigned long sunxi_dram_init(void)
>>  	mctl_auto_detect_dram_size(socid, &para);
>>  	mctl_set_cr(socid, &para);
>> 
>> -	return (1UL << (para.row_bits + para.bank_bits)) * para.page_size *
>> +	return (1ULL << (para.row_bits + para.bank_bits)) * para.page_size *
>>  	       (para.dual_rank ? 2 : 1);
>>  }
>> diff --git a/board/sunxi/board.c b/board/sunxi/board.c
>> index 8d707cbac2..5828d47294 100644
>> --- a/board/sunxi/board.c
>> +++ b/board/sunxi/board.c
>> @@ -601,7 +601,7 @@ void sunxi_board_init(void)
>>  #endif
>>  #endif
>>  	printf("DRAM:");
>> -	gd->ram_size = sunxi_dram_init();
>> +	gd->ram_size = (phys_size_t)sunxi_dram_init();
>>  	printf(" %d MiB\n", (int)(gd->ram_size >> 20));
>>  	if (!gd->ram_size)
>>  		hang();
>> diff --git a/board/sunxi/dram_sun4i_auto.c 
>> b/board/sunxi/dram_sun4i_auto.c
>> index 7d4409b51e..293c968f6b 100644
>> --- a/board/sunxi/dram_sun4i_auto.c
>> +++ b/board/sunxi/dram_sun4i_auto.c
>> @@ -29,7 +29,7 @@ static struct dram_para dram_para = {
>>  	.dqs_gating_delay = CONFIG_DRAM_DQS_GATING_DELAY,
>>  };
>> 
>> -unsigned long sunxi_dram_init(void)
>> +unsigned long long sunxi_dram_init(void)
>>  {
>>  	return dramc_init(&dram_para);
>>  }
>> diff --git a/board/sunxi/dram_sun5i_auto.c 
>> b/board/sunxi/dram_sun5i_auto.c
>> index e3fa243267..02e29b215f 100644
>> --- a/board/sunxi/dram_sun5i_auto.c
>> +++ b/board/sunxi/dram_sun5i_auto.c
>> @@ -32,7 +32,7 @@ static struct dram_para dram_para = {
>>  	.dqs_gating_delay = CONFIG_DRAM_DQS_GATING_DELAY,
>>  };
>> 
>> -unsigned long sunxi_dram_init(void)
>> +unsigned long long sunxi_dram_init(void)
>>  {
>>  	return dramc_init(&dram_para);
>>  }
>> 


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