From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752645AbcFCQI7 (ORCPT ); Fri, 3 Jun 2016 12:08:59 -0400 Received: from mail-pa0-f41.google.com ([209.85.220.41]:35835 "EHLO mail-pa0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752332AbcFCQI5 (ORCPT ); Fri, 3 Jun 2016 12:08:57 -0400 From: Gwendal Grignou To: ulf.hansson@linaro.org Cc: grundler@chromium.org, axboe@kernel.dk, linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v3] CHROMIUM: mmc: Set pref erase size based on size. Date: Fri, 3 Jun 2016 09:08:52 -0700 Message-Id: <1464970132-26197-1-git-send-email-gwendal@chromium.org> X-Mailer: git-send-email 2.8.0.rc3.226.g39d4020 In-Reply-To: <1464913638-5283-1-git-send-email-gwendal@chromium.org> References: <1464913638-5283-1-git-send-email-gwendal@chromium.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If available, eMMC stack uses HC_ERASE_GRP_SIZE as erase size. The perfererred erase size may need to be bigger to ensure discard operations are not too slow. Some high capacity eMMC (64MB) reports erase size to 512kB, resulting in long discard time. Calculate prefeerred erase size based on eMMC size. Signed-off-by: Gwendal Grignou --- v2: fix comments v3: rereading the patch, we should not compare to hc_erase_size again, it has already been set properly in the caller function. drivers/mmc/core/core.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index ef76b1c..bd881a0 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -1987,17 +1987,17 @@ void mmc_init_erase(struct mmc_card *card) * to that size and alignment. * * For SD cards that define Allocation Unit size, limit erases to one - * Allocation Unit at a time. For MMC cards that define High Capacity - * Erase Size, whether it is switched on or not, limit to that size. - * Otherwise just have a stab at a good value. For modern cards it - * will end up being 4MiB. Note that if the value is too small, it - * can end up taking longer to erase. + * Allocation Unit at a time. + * For MMC, have a stab at a good value. For modern cards it + * will end up being 4MiB. + * Note that if the value is too small, it can end up taking longer to + * erase. + * erase_size is already set to High Capacity Erase Size if available + * when this function is called. */ if (mmc_card_sd(card) && card->ssr.au) { card->pref_erase = card->ssr.au; card->erase_shift = ffs(card->ssr.au) - 1; - } else if (card->ext_csd.hc_erase_size) { - card->pref_erase = card->ext_csd.hc_erase_size; } else if (card->erase_size) { sz = (card->csd.capacity << (card->csd.read_blkbits - 9)) >> 11; if (sz < 128) -- 2.8.0.rc3.226.g39d4020