diff options
| -rw-r--r-- | drivers/mmc/core/core.c | 29 | ||||
| -rw-r--r-- | drivers/mmc/core/sdio_io.c | 99 | ||||
| -rw-r--r-- | drivers/net/wireless/libertas/if_sdio.c | 20 | ||||
| -rw-r--r-- | include/linux/mmc/core.h | 1 | ||||
| -rw-r--r-- | include/linux/mmc/sdio_func.h | 4 |
5 files changed, 137 insertions, 16 deletions
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index ede5d1e2e20..3ee5b8c3b5c 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -3,7 +3,7 @@ * * Copyright (C) 2003-2004 Russell King, All Rights Reserved. * SD support Copyright (C) 2004 Ian Molton, All Rights Reserved. - * Copyright (C) 2005-2007 Pierre Ossman, All Rights Reserved. + * Copyright (C) 2005-2008 Pierre Ossman, All Rights Reserved. * MMCv4 support Copyright (C) 2006 Philip Langdale, All Rights Reserved. * * This program is free software; you can redistribute it and/or modify @@ -295,6 +295,33 @@ void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card) EXPORT_SYMBOL(mmc_set_data_timeout); /** + * mmc_align_data_size - pads a transfer size to a more optimal value + * @card: the MMC card associated with the data transfer + * @sz: original transfer size + * + * Pads the original data size with a number of extra bytes in + * order to avoid controller bugs and/or performance hits + * (e.g. some controllers revert to PIO for certain sizes). + * + * Returns the improved size, which might be unmodified. + * + * Note that this function is only relevant when issuing a + * single scatter gather entry. + */ +unsigned int mmc_align_data_size(struct mmc_card *card, unsigned int sz) +{ + /* + * FIXME: We don't have a system for the controller to tell + * the core about its problems yet, so for now we just 32-bit + * align the size. + */ + sz = ((sz + 3) / 4) * 4; + + return sz; +} +EXPORT_SYMBOL(mmc_align_data_size); + +/** * __mmc_claim_host - exclusively claim a host * @host: mmc host to claim * @abort: whether or not the operation should be aborted diff --git a/drivers/mmc/core/sdio_io.c b/drivers/mmc/core/sdio_io.c index 625b92ce9ce..6ee7861fcea 100644 --- a/drivers/mmc/core/sdio_io.c +++ b/drivers/mmc/core/sdio_io.c @@ -1,7 +1,7 @@ /* * linux/drivers/mmc/core/sdio_io.c * - * Copyright 2007 Pierre Ossman + * Copyright 2007-2008 Pierre Ossman * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -189,6 +189,103 @@ int sdio_set_block_size(struct sdio_func *func, unsigned blksz) EXPORT_SYMBOL_GPL(sdio_set_block_size); +/** + * sdio_align_size - pads a transfer size to a more optimal value + * @func: SDIO function + * @sz: original transfer size + * + * Pads the original data size with a number of extra bytes in + * order to avoid controller bugs and/or performance hits + * (e.g. some controllers revert to PIO for certain sizes). + * + * If possible, it will also adjust the size so that it can be + * handled in just a single request. + * + * Returns the improved size, which might be unmodified. + */ +unsigned int sdio_align_size(struct sdio_func *func, unsigned int sz) +{ + unsigned int orig_sz; + unsigned int blk_sz, byte_sz; + unsigned chunk_sz; + + orig_sz = sz; + + /* + * Do a first check with the controller, in case it + * wants to increase the size up to a point where it + * might need more than one block. + */ + sz = mmc_align_data_size(func->card, sz); + + /* + * If we can still do this with just a byte transfer, then + * we're done. + */ + if ((sz <= func->cur_blksize) && (sz <= 512)) + return sz; + + if (func->card->cccr.multi_block) { + /* + * Check if the transfer is already block aligned + */ + if ((sz % func->cur_blksize) == 0) + return sz; + + /* + * Realign it so that it can be done with one request, + * and recheck if the controller still likes it. + */ + blk_sz = ((sz + func->cur_blksize - 1) / + func->cur_blksize) * func->cur_blksize; + blk_sz = mmc_align_data_size(func->card, blk_sz); + + /* + * This value is only good if it is still just + * one request. + */ + if ((blk_sz % func->cur_blksize) == 0) + return blk_sz; + + /* + * We failed to do one request, but at least try to + * pad the remainder properly. + */ + byte_sz = mmc_align_data_size(func->card, + sz % func->cur_blksize); + if ((byte_sz <= func->cur_blksize) && (byte_sz <= 512)) { + blk_sz = sz / func->cur_blksize; + return blk_sz * func->cur_blksize + byte_sz; + } + } else { + /* + * We need multiple requests, so first check that the + * controller can handle the chunk size; + */ + chunk_sz = mmc_align_data_size(func->card, + min(func->cur_blksize, 512u)); + if (chunk_sz == min(func->cur_blksize, 512u)) { + /* + * Fix up the size of the remainder (if any) + */ + byte_sz = orig_sz % chunk_sz; + if (byte_sz) { + byte_sz = mmc_align_data_size(func->card, + byte_sz); + } + + return (orig_sz / chunk_sz) * chunk_sz + byte_sz; + } + } + + /* + * The controller is simply incapable of transferring the size + * we want in decent manner, so just return the original size. + */ + return orig_sz; +} +EXPORT_SYMBOL_GPL(sdio_align_size); + /* Split an arbitrarily sized data transfer into several * IO_RW_EXTENDED commands. */ static int sdio_io_rw_ext_helper(struct sdio_func *func, int write, diff --git a/drivers/net/wireless/libertas/if_sdio.c b/drivers/net/wireless/libertas/if_sdio.c index 3dd537be87d..b54e2ea8346 100644 --- a/drivers/net/wireless/libertas/if_sdio.c +++ b/drivers/net/wireless/libertas/if_sdio.c @@ -1,7 +1,7 @@ /* * linux/drivers/net/wireless/libertas/if_sdio.c * - * Copyright 2007 Pierre Ossman + * Copyright 2007-2008 Pierre Ossman * * Inspired by if_cs.c, Copyright 2007 Holger Schurig * @@ -266,13 +266,10 @@ static int if_sdio_card_to_host(struct if_sdio_card *card) /* * The transfer must be in one transaction or the firmware - * goes suicidal. + * goes suicidal. There's no way to guarantee that for all + * controllers, but we can at least try. */ - chunk = size; - if ((chunk > card->func->cur_blksize) || (chunk > 512)) { - chunk = (chunk + card->func->cur_blksize - 1) / - card->func->cur_blksize * card->func->cur_blksize; - } + chunk = sdio_align_size(card->func, size); ret = sdio_readsb(card->func, card->buffer, card->ioport, chunk); if (ret) @@ -696,13 +693,10 @@ static int if_sdio_host_to_card(struct lbs_private *priv, /* * The transfer must be in one transaction or the firmware - * goes suicidal. + * goes suicidal. There's no way to guarantee that for all + * controllers, but we can at least try. */ - size = nb + 4; - if ((size > card->func->cur_blksize) || (size > 512)) { - size = (size + card->func->cur_blksize - 1) / - card->func->cur_blksize * card->func->cur_blksize; - } + size = sdio_align_size(card->func, nb + 4); packet = kzalloc(sizeof(struct if_sdio_packet) + size, GFP_ATOMIC); diff --git a/include/linux/mmc/core.h b/include/linux/mmc/core.h index d0c3abed74c..143cebf0586 100644 --- a/include/linux/mmc/core.h +++ b/include/linux/mmc/core.h @@ -135,6 +135,7 @@ extern int mmc_wait_for_app_cmd(struct mmc_host *, struct mmc_card *, struct mmc_command *, int); extern void mmc_set_data_timeout(struct mmc_data *, const struct mmc_card *); +extern unsigned int mmc_align_data_size(struct mmc_card *, unsigned int); extern int __mmc_claim_host(struct mmc_host *host, atomic_t *abort); extern void mmc_release_host(struct mmc_host *host); diff --git a/include/linux/mmc/sdio_func.h b/include/linux/mmc/sdio_func.h index b050f4d7b41..f57f22b3be8 100644 --- a/include/linux/mmc/sdio_func.h +++ b/include/linux/mmc/sdio_func.h @@ -1,7 +1,7 @@ /* * include/linux/mmc/sdio_func.h * - * Copyright 2007 Pierre Ossman + * Copyright 2007-2008 Pierre Ossman * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -120,6 +120,8 @@ extern int sdio_set_block_size(struct sdio_func *func, unsigned blksz); extern int sdio_claim_irq(struct sdio_func *func, sdio_irq_handler_t *handler); extern int sdio_release_irq(struct sdio_func *func); +extern unsigned int sdio_align_size(struct sdio_func *func, unsigned int sz); + extern unsigned char sdio_readb(struct sdio_func *func, unsigned int addr, int *err_ret); extern unsigned short sdio_readw(struct sdio_func *func, |