Read function tested for chunk size 62 and with start offset 3, works as expected.
Signed-off-by: Michael Karcher flashrom@mkarcher.dialup.fu-berlin.de --- spi25.c | 80 +++++++++++++++++++++++++------------------------------------- 1 files changed, 32 insertions(+), 48 deletions(-)
diff --git a/spi25.c b/spi25.c index 51be397..260dd1c 100644 --- a/spi25.c +++ b/spi25.c @@ -879,35 +879,27 @@ int spi_nbyte_read(int address, uint8_t *bytes, int len) int spi_read_chunked(struct flashchip *flash, uint8_t *buf, int start, int len, int chunksize) { int rc = 0; - int i, j, starthere, lenhere; + int ofs, startofs, endofs; /* offsets relative to page begin */ int page_size = flash->page_size; - int toread; - - /* Warning: This loop has a very unusual condition and body. - * The loop needs to go through each page with at least one affected - * byte. The lowest page number is (start / page_size) since that - * division rounds down. The highest page number we want is the page - * where the last byte of the range lives. That last byte has the - * address (start + len - 1), thus the highest page number is - * (start + len - 1) / page_size. Since we want to include that last - * page as well, the loop condition uses <=. - */ - for (i = start / page_size; i <= (start + len - 1) / page_size; i++) { - /* Byte position of the first byte in the range in this page. */ - /* starthere is an offset to the base address of the chip. */ - starthere = max(start, i * page_size); - /* Length of bytes in the range in this page. */ - lenhere = min(start + len, (i + 1) * page_size) - starthere; - for (j = 0; j < lenhere; j += chunksize) { - toread = min(chunksize, lenhere - j); - rc = spi_nbyte_read(starthere + j, buf + starthere - start + j, toread); + int pageaddr, toread; + + startofs = start % page_size; + /* iterate over all affected pages */ + for (pageaddr = start - startofs; pageaddr < start + len; + pageaddr += page_size) { + endofs = min(page_size, start + len - pageaddr); + /* iterate over all chunks in the current page */ + for (ofs = startofs; ofs < endofs; ofs += chunksize) { + toread = min(chunksize, endofs - ofs); + rc = spi_nbyte_read(pageaddr + ofs, buf, toread); + buf += toread; if (rc) - break; + goto leave_page_loop; } - if (rc) - break; + startofs = 0; /* all further pages processed from start */ }
+leave_page_loop: return rc; }
@@ -918,42 +910,34 @@ int spi_read_chunked(struct flashchip *flash, uint8_t *buf, int start, int len, int spi_write_chunked(struct flashchip *flash, uint8_t *buf, int start, int len, int chunksize) { int rc = 0; - int i, j, starthere, lenhere; + int ofs, startofs, endofs; /* offsets relative to page begin */ /* FIXME: page_size is the wrong variable. We need max_writechunk_size * in struct flashchip to do this properly. All chips using * spi_chip_write_256 have page_size set to max_writechunk_size, so * we're OK for now. */ int page_size = flash->page_size; - int towrite; - - /* Warning: This loop has a very unusual condition and body. - * The loop needs to go through each page with at least one affected - * byte. The lowest page number is (start / page_size) since that - * division rounds down. The highest page number we want is the page - * where the last byte of the range lives. That last byte has the - * address (start + len - 1), thus the highest page number is - * (start + len - 1) / page_size. Since we want to include that last - * page as well, the loop condition uses <=. - */ - for (i = start / page_size; i <= (start + len - 1) / page_size; i++) { - /* Byte position of the first byte in the range in this page. */ - /* starthere is an offset to the base address of the chip. */ - starthere = max(start, i * page_size); - /* Length of bytes in the range in this page. */ - lenhere = min(start + len, (i + 1) * page_size) - starthere; - for (j = 0; j < lenhere; j += chunksize) { - towrite = min(chunksize, lenhere - j); - rc = spi_nbyte_program(starthere + j, buf + starthere - start + j, towrite); + int pageaddr, towrite; + + startofs = start % page_size; + /* iterate over all affected pages */ + for (pageaddr = start - startofs; pageaddr < start + len; + pageaddr += page_size) { + endofs = min(page_size, start + len - pageaddr); + /* iterate over all chunks in the current page */ + for (ofs = startofs; ofs < endofs; ofs += chunksize) { + towrite = min(chunksize, endofs - ofs); + rc = spi_nbyte_program(pageaddr + ofs, buf, towrite); + buf += towrite; if (rc) - break; + goto leave_page_loop; while (spi_read_status_register() & JEDEC_RDSR_BIT_WIP) programmer_delay(10); } - if (rc) - break; + startofs = 0; /* all further pages processed from start */ }
+leave_page_loop: return rc; }