[J-u-boot.git] / doc / README.omap3


Summary
=======

This README is about U-Boot support for TI's ARM Cortex-A8 based OMAP3 [1]
family of SoCs. TI's OMAP3 SoC family contains an ARM Cortex-A8. Additionally,
some family members contain a TMS320C64x+ DSP and/or an Imagination SGX 2D/3D
graphics processor and various other standard peripherals.

Currently the following boards are supported:

* OMAP3530 BeagleBoard [2]

* Gumstix Overo [3]

* TI EVM [4]

* OpenPandora Ltd. Pandora [5]

* TI/Logic PD Zoom MDK [6]

* TI/Logic PD Zoom 2 [7]

* CompuLab Ltd. CM-T35 [8]

Build
=====

* BeagleBoard:

make omap3_beagle_config
make

* Gumstix Overo:

make omap3_overo_config
make

* TI EVM:

make omap3_evm_config
make

* Zoom 2:

make omap3_zoom2_config
make

* CM-T35:

make cm_t35_config
make


Custom commands
===============

To make U-Boot for OMAP3 support NAND device SW or HW ECC calculation, U-Boot
for OMAP3 supports custom user command

nandecc hw/sw

To be compatible with NAND drivers using SW ECC (e.g. kernel code)

nandecc sw

enables SW ECC calculation. HW ECC enabled with

nandecc hw

is typically used to write 2nd stage bootloader (known as 'x-loader') which is
executed by OMAP3's boot rom and therefore has to be written with HW ECC.

For all other commands see

help

Interfaces
==========

gpio
----

To set a bit :

	if (!gpio_request(N, "")) {
		gpio_direction_output(N, 0);
		gpio_set_value(N, 1);
	}

To clear a bit :

	if (!gpio_request(N, "")) {
		gpio_direction_output(N, 0);
		gpio_set_value(N, 0);
	}

To read a bit :

	if (!gpio_request(N, "")) {
		gpio_direction_input(N);
		val = gpio_get_value(N);
		gpio_free(N);
	}
	if (val)
		printf("GPIO N is set\n");
	else
		printf("GPIO N is clear\n");

dma
---
void omap3_dma_init(void)
	Init the DMA module
int omap3_dma_get_conf_chan(uint32_t chan, struct dma4_chan *config);
	Read config of the channel
int omap3_dma_conf_chan(uint32_t chan, struct dma4_chan *config);
	Write config to the channel
int omap3_dma_conf_transfer(uint32_t chan, uint32_t *src, uint32_t *dst,
		uint32_t sze)
	Config source, destination and size of a transfer
int omap3_dma_wait_for_transfer(uint32_t chan)
	Wait for a transfer to end - this hast to be called before a channel
	or the data the channel transferd are used.
int omap3_dma_get_revision(uint32_t *minor, uint32_t *major)
	Read silicon Revision of the DMA module

NAND
====

There are some OMAP3 devices out there with NAND attached. Due to the fact that
OMAP3 ROM code can only handle 1-bit hamming ECC for accessing first page
(place where SPL lives) we require this setup for u-boot at least when reading
the second progam within SPL.  A lot of newer NAND chips however require more
than 1-bit ECC for the pages, some can live with 1-bit for the first page. To
handle this we can switch to another ECC algorithm after reading the payload
within SPL.

BCH8
----

To enable hardware assisted BCH8 (8-bit BCH [Bose, Chaudhuri, Hocquenghem]) on
OMAP3 devices we can use the BCH library in lib/bch.c. To do so add CONFIG_BCH
and set CONFIG_NAND_OMAP_ECCSCHEME=5 (refer README.nand) for selecting BCH8_SW.
The NAND OOB layout is the same as in linux kernel, if the linux kernel BCH8
implementation for OMAP3 works for you so the u-boot version should also.
When you require the SPL to read with BCH8 there are two more configs to
change:

 * CONFIG_SYS_NAND_ECCPOS (must be the same as .eccpos in
   GPMC_NAND_HW_BCH8_ECC_LAYOUT defined in
   arch/arm/include/asm/arch-omap3/omap_gpmc.h)
 * CONFIG_SYS_NAND_ECCSIZE must be 512
 * CONFIG_SYS_NAND_ECCBYTES must be 13 for this BCH8 setup

Acknowledgements
================

OMAP3 U-Boot is based on U-Boot tar ball [9] for BeagleBoard and EVM done by
several TI employees.

Links
=====

[1] OMAP3:

http://www.ti.com/omap3 (high volume) and
http://www.ti.com/omap35x (broad market)

[2] OMAP3530 BeagleBoard:

http://beagleboard.org/

[3] Gumstix Overo:

http://www.gumstix.net/Overo/

[4] TI EVM:

http://focus.ti.com/docs/toolsw/folders/print/tmdxevm3503.html

[5] OpenPandora Ltd. Pandora:

http://openpandora.org/

[6] TI/Logic PD Zoom MDK:

http://www.logicpd.com/products/devkit/ti/zoom_mobile_development_kit

[7] TI/Logic PD Zoom 2

http://www.logicpd.com/sites/default/files/1012659A_Zoom_OMAP34x-II_MDP_Brief.pdf

[8] CompuLab Ltd. CM-T35:

http://www.compulab.co.il/t3530/html/t3530-cm-datasheet.htm

[9] TI OMAP3 U-Boot:

http://beagleboard.googlecode.com/files/u-boot_beagle_revb.tar.gz
Commit	Line	Data
f904cdbb DB	1
	2	Summary
	3	=======
	4
	5	This README is about U-Boot support for TI's ARM Cortex-A8 based OMAP3 [1]
	6	family of SoCs. TI's OMAP3 SoC family contains an ARM Cortex-A8. Additionally,
	7	some family members contain a TMS320C64x+ DSP and/or an Imagination SGX 2D/3D
	8	graphics processor and various other standard peripherals.
	9
	10	Currently the following boards are supported:
	11
	12	* OMAP3530 BeagleBoard [2]
	13
9d0fc811 DB	14	* Gumstix Overo [3]
9d0fc811 DB	15
ad9bc8e5 DB	16	* TI EVM [4]
ad9bc8e5 DB	17
2be2c6cc DB	18	* OpenPandora Ltd. Pandora [5]
2be2c6cc DB	19
7379f45a DB	20	* TI/Logic PD Zoom MDK [6]
7379f45a DB	21
376aee78 TR	22	* TI/Logic PD Zoom 2 [7]
376aee78 TR	23
36b4e2dd MR	24	* CompuLab Ltd. CM-T35 [8]
36b4e2dd MR	25
f904cdbb DB	26	Build
	27	=====
	28
	29	* BeagleBoard:
	30
	31	make omap3_beagle_config
	32	make
	33
9d0fc811 DB	34	* Gumstix Overo:
	35
	36	make omap3_overo_config
	37	make
	38
ad9bc8e5 DB	39	* TI EVM:
	40
	41	make omap3_evm_config
	42	make
	43
376aee78 TR	44	* Zoom 2:
	45
	46	make omap3_zoom2_config
	47	make
	48
36b4e2dd MR	49	* CM-T35:
	50
	51	make cm_t35_config
	52	make
	53
84d7a017	54
f904cdbb DB	55	Custom commands
	56	===============
	57
	58	To make U-Boot for OMAP3 support NAND device SW or HW ECC calculation, U-Boot
	59	for OMAP3 supports custom user command
	60
	61	nandecc hw/sw
	62
	63	To be compatible with NAND drivers using SW ECC (e.g. kernel code)
	64
	65	nandecc sw
	66
	67	enables SW ECC calculation. HW ECC enabled with
	68
	69	nandecc hw
	70
	71	is typically used to write 2nd stage bootloader (known as 'x-loader') which is
	72	executed by OMAP3's boot rom and therefore has to be written with HW ECC.
	73
	74	For all other commands see
	75
	76	help
	77
0c872ecd TR	78	Interfaces
	79	==========
	80
	81	gpio
4c4bb19d	82	----
0c872ecd TR	83
	84	To set a bit :
	85
3b690ebb SP	86	if (!gpio_request(N, "")) {
	87	gpio_direction_output(N, 0);
	88	gpio_set_value(N, 1);
0c872ecd TR	89	}
	90
	91	To clear a bit :
	92
3b690ebb SP	93	if (!gpio_request(N, "")) {
	94	gpio_direction_output(N, 0);
	95	gpio_set_value(N, 0);
0c872ecd TR	96	}
	97
	98	To read a bit :
	99
3b690ebb SP	100	if (!gpio_request(N, "")) {
	101	gpio_direction_input(N);
	102	val = gpio_get_value(N);
	103	gpio_free(N);
0c872ecd TR	104	}
	105	if (val)
	106	printf("GPIO N is set\n");
	107	else
	108	printf("GPIO N is clear\n");
	109
4c4bb19d SS	110	dma
	111	---
	112	void omap3_dma_init(void)
	113	Init the DMA module
	114	int omap3_dma_get_conf_chan(uint32_t chan, struct dma4_chan *config);
	115	Read config of the channel
	116	int omap3_dma_conf_chan(uint32_t chan, struct dma4_chan *config);
	117	Write config to the channel
	118	int omap3_dma_conf_transfer(uint32_t chan, uint32_t src, uint32_t dst,
	119	uint32_t sze)
	120	Config source, destination and size of a transfer
	121	int omap3_dma_wait_for_transfer(uint32_t chan)
	122	Wait for a transfer to end - this hast to be called before a channel
	123	or the data the channel transferd are used.
	124	int omap3_dma_get_revision(uint32_t minor, uint32_t major)
	125	Read silicon Revision of the DMA module
	126
4a093006 AB	127	NAND
	128	====
	129
	130	There are some OMAP3 devices out there with NAND attached. Due to the fact that
	131	OMAP3 ROM code can only handle 1-bit hamming ECC for accessing first page
	132	(place where SPL lives) we require this setup for u-boot at least when reading
	133	the second progam within SPL. A lot of newer NAND chips however require more
	134	than 1-bit ECC for the pages, some can live with 1-bit for the first page. To
	135	handle this we can switch to another ECC algorithm after reading the payload
	136	within SPL.
	137
	138	BCH8
	139	----
	140
	141	To enable hardware assisted BCH8 (8-bit BCH [Bose, Chaudhuri, Hocquenghem]) on
	142	OMAP3 devices we can use the BCH library in lib/bch.c. To do so add CONFIG_BCH
3f719069	143	and set CONFIG_NAND_OMAP_ECCSCHEME=5 (refer README.nand) for selecting BCH8_SW.
4a093006 AB	144	The NAND OOB layout is the same as in linux kernel, if the linux kernel BCH8
	145	implementation for OMAP3 works for you so the u-boot version should also.
	146	When you require the SPL to read with BCH8 there are two more configs to
	147	change:
	148
	149	* CONFIG_SYS_NAND_ECCPOS (must be the same as .eccpos in
	150	GPMC_NAND_HW_BCH8_ECC_LAYOUT defined in
	151	arch/arm/include/asm/arch-omap3/omap_gpmc.h)
	152	* CONFIG_SYS_NAND_ECCSIZE must be 512
	153	* CONFIG_SYS_NAND_ECCBYTES must be 13 for this BCH8 setup
0c872ecd	154
f904cdbb DB	155	Acknowledgements
	156	================
	157
36b4e2dd	158	OMAP3 U-Boot is based on U-Boot tar ball [9] for BeagleBoard and EVM done by
f904cdbb DB	159	several TI employees.
	160
	161	Links
	162	=====
	163
	164	[1] OMAP3:
	165
	166	http://www.ti.com/omap3 (high volume) and
	167	http://www.ti.com/omap35x (broad market)
	168
	169	[2] OMAP3530 BeagleBoard:
	170
	171	http://beagleboard.org/
	172
9d0fc811 DB	173	[3] Gumstix Overo:
	174
	175	http://www.gumstix.net/Overo/
	176
ad9bc8e5 DB	177	[4] TI EVM:
	178
	179	http://focus.ti.com/docs/toolsw/folders/print/tmdxevm3503.html
	180
2be2c6cc DB	181	[5] OpenPandora Ltd. Pandora:
	182
	183	http://openpandora.org/
	184
7379f45a DB	185	[6] TI/Logic PD Zoom MDK:
	186
	187	http://www.logicpd.com/products/devkit/ti/zoom_mobile_development_kit
	188
376aee78 TR	189	[7] TI/Logic PD Zoom 2
	190
	191	http://www.logicpd.com/sites/default/files/1012659A_Zoom_OMAP34x-II_MDP_Brief.pdf
36b4e2dd MR	192
	193	[8] CompuLab Ltd. CM-T35:
	194
	195	http://www.compulab.co.il/t3530/html/t3530-cm-datasheet.htm
	196
	197	[9] TI OMAP3 U-Boot:
f904cdbb DB	198
f904cdbb DB	199	http://beagleboard.googlecode.com/files/u-boot_beagle_revb.tar.gz