Re: [PATCH v2 1/7] misc: ddr: add LPDDR2 data from JESD209-2

[Aneesh V <aneesh@ti.com>]

On Friday 16 March 2012 12:32 AM, Greg KH wrote:
> On Thu, Mar 15, 2012 at 11:47:31PM +0530, Aneesh V wrote:
>> add LPDDR2 data from the JEDEC spec JESD209-2. The data
>> includes:
>>
>> 1. Addressing information for LPDDR2 memories of different
>>     densities and types(S2/S4)
>> 2. AC timing data.
>>
>> This data will useful for memory controller device drivers
>
> Right now, only one driver, right?

Yes, should that be documented?

>
>> +#ifndef __ASSEMBLY__
>
> Why is this needed?

IIRC, this header file was getting included in an omap specific header
file that was in turn included from an assembly file. I will check if
this is still the case. If not, I will remove it.

>
>> +/* Structure for DDR addressing info from the JEDEC spec */
>> +struct lpddr2_addressing {
>> +	u32 num_banks;
>> +	u32 tREFI_ns;
>> +	u32 tRFCab_ps;
>> +};
>
> Do these structures cross the user/kernel boundry somehow?  If so,
> please use the proper kernel types for this.

No. These structures are meant for use by device drivers.

>
>> --- a/lib/Makefile
>> +++ b/lib/Makefile
>> @@ -123,6 +123,9 @@ obj-$(CONFIG_SIGNATURE) += digsig.o
>>
>>   obj-$(CONFIG_CLZ_TAB) += clz_tab.o
>>
>> +obj-$(CONFIG_DDR) += jedec_ddr_data.o
>> +
>> +
>
> Why the extra line?

Un-intentional. Will remove.

>
>>   hostprogs-y	:= gen_crc32table
>>   clean-files	:= crc32table.h
>>
>> diff --git a/lib/jedec_ddr_data.c b/lib/jedec_ddr_data.c
>> new file mode 100644
>> index 0000000..fc223d6
>> --- /dev/null
>> +++ b/lib/jedec_ddr_data.c
>> @@ -0,0 +1,135 @@
>> +/*
>> + * DDR addressing details and AC timing parameters from JEDEC specs
>> + *
>> + * Copyright (C) 2012 Texas Instruments, Inc.
>> + *
>> + * Aneesh V<aneesh@ti.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<misc/jedec_ddr.h>
>> +#include<linux/module.h>
>> +
>> +/* LPDDR2 addressing details from JESD209-2 section 2.4 */
>> +const struct lpddr2_addressing
>> +	lpddr2_jedec_addressing_table[NUM_DDR_ADDR_TABLE_ENTRIES] = {
>> +	{B4, T_REFI_15_6, T_RFC_90}, /* 64M */
>> +	{B4, T_REFI_15_6, T_RFC_90}, /* 128M */
>> +	{B4, T_REFI_7_8,  T_RFC_90}, /* 256M */
>> +	{B4, T_REFI_7_8,  T_RFC_90}, /* 512M */
>> +	{B8, T_REFI_7_8, T_RFC_130}, /* 1GS4 */
>> +	{B8, T_REFI_3_9, T_RFC_130}, /* 2GS4 */
>> +	{B8, T_REFI_3_9, T_RFC_130}, /* 4G */
>> +	{B8, T_REFI_3_9, T_RFC_210}, /* 8G */
>> +	{B4, T_REFI_7_8, T_RFC_130}, /* 1GS2 */
>> +	{B4, T_REFI_3_9, T_RFC_130}, /* 2GS2 */
>> +};
>> +EXPORT_SYMBOL(lpddr2_jedec_addressing_table);
>
> EXPORT_SYMBOL_GPL for these and the others?

Will fix all.

Thanks,
Aneesh