| New C structure AT91 SoC access |
| ================================= |
| |
| The goal |
| -------- |
| |
| Currently the at91 arch uses hundreds of address defines and special |
| at91_xxxx_write/read functions to access the SOC. |
| The u-boot project perferred method is to access memory mapped hw |
| regisister via a c structure. |
| |
| e.g. old |
| |
| *AT91C_PIOA_IDR = AT91_PMX_AA_TWD | AT91_PMX_AA_TWCK; |
| *AT91C_PIOC_PUDR = AT91_PMX_AA_TWD | AT91_PMX_AA_TWCK; |
| *AT91C_PIOC_PER = AT91_PMX_AA_TWD | AT91_PMX_AA_TWCK; |
| *AT91C_PIOC_OER = AT91_PMX_AA_TWD | AT91_PMX_AA_TWCK; |
| *AT91C_PIOC_PIO = AT91_PMX_AA_TWD | AT91_PMX_AA_TWCK; |
| |
| at91_sys_write(AT91_RSTC_CR, |
| AT91_RSTC_KEY | AT91_RSTC_PROCRST | AT91_RSTC_PERRST); |
| |
| e.g new |
| pin = AT91_PMX_AA_TWD | AT91_PMX_AA_TWCK; |
| writel(pin, &pio->pioa.idr); |
| writel(pin, &pio->pioa.pudr); |
| writel(pin, &pio->pioa.per); |
| writel(pin, &pio->pioa.oer); |
| writel(pin, &pio->pioa.sodr); |
| |
| writel(AT91_RSTC_KEY | AT91_RSTC_CR_PROCRST | |
| AT91_RSTC_CR_PERRST, &rstc->cr); |
| |
| The method for updating |
| ------------------------ |
| |
| 1. add's the temporary CONFIG_AT91_LEGACY to all at91 board configs |
| 2. Display a compile time warning, if the board has not been converted |
| 3. add new structures for SoC access |
| 4. Convert arch, driver and boards file to new SoC |
| 5. remove legacy code, if all boards and drives are ready |
| |
| 2013-10-30 Andreas Bießmann <andreas.devel@googlemail.com>: |
| |
| The goal is almost reached, we could remove the CONFIG_AT91_LEGACY switch but |
| remain the CONFIG_ATMEL_LEGACY switch until the GPIO disaster is fixed. The |
| AT91 spi driver has also some CONFIG_ATMEL_LEGACY stuff left, so another point |
| to fix until this README can be removed. |
