Add additional SPI sector erase and chip erase command functions

Not all chips support all commands, so allow the implementer to select
the matching function. Fix a layering violation in ICH SPI code to be
less bad. Still not perfect, but the new code is shorter, more generic
and architecturally more sound.

TODO (in a separate patch): - move the generic sector erase code to
spi.c - decide which erase command to use based on info about the chip -
create a generic spi_erase_all_sectors function which calls the generic
sector erase function

Thanks to Stefan for reviewing and commenting.

Corresponding to flashrom svn r337 and coreboot v2 svn r3722.

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Acked-by: Stefan Reinauer <stepan@coresystems.de>
diff --git a/flash.h b/flash.h
index 769b8d0..5010837 100644
--- a/flash.h
+++ b/flash.h
@@ -424,8 +424,11 @@
 		const unsigned char *writearr, unsigned char *readarr);
 void spi_write_enable();
 void spi_write_disable();
+int spi_chip_erase_60(struct flashchip *flash);
 int spi_chip_erase_c7(struct flashchip *flash);
 int spi_chip_erase_d8(struct flashchip *flash);
+int spi_block_erase_52(const struct flashchip *flash, unsigned long addr);
+int spi_block_erase_d8(const struct flashchip *flash, unsigned long addr);
 int spi_chip_write(struct flashchip *flash, uint8_t *buf);
 int spi_chip_read(struct flashchip *flash, uint8_t *buf);
 uint8_t spi_read_status_register();