From mboxrd@z Thu Jan 1 00:00:00 1970 From: Reinhard Meyer Date: Mon, 06 Sep 2010 11:23:46 +0200 Subject: [U-Boot] [PATCH] mmc: seperate block number into small parts for multi-write cmd In-Reply-To: <1283757567-15161-1-git-send-email-leiwen@marvell.com> References: <1283757567-15161-1-git-send-email-leiwen@marvell.com> Message-ID: <4C84B322.1000500@emk-elektronik.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Dear Lei Wen, > As mmc host limitation, the max number of block in one go > should be limited to 65535, and the max buffer size should > not excceed 512k bytes. Where does this limitation supposedly come from? And, 65535 blocks (of 512) are already near 32 MB. TOP9000> mmci mci: setting clock 194000 Hz, block size 512 mci: setting clock 24832000 Hz, block size 512 mci: setting clock 194000 Hz, block size 512 mci: setting clock 194000 Hz, block size 512 mci: setting clock 24832000 Hz, block size 512 Device: mci Manufacturer ID: 3 OEM: 5344 Name: SD32G Tran Speed: 25000000 Rd Block Len: 512 SD version 2.0 High Capacity: Yes Capacity: 31914983424 Bus Width: 4-bit TOP9000> mmc write 0 20000000 1000 18000 MMC write: dev # 0, block # 4096, count 98304 ... mci: setting clock 194000 Hz, block size 512 mci: setting clock 24832000 Hz, block size 512 mci: setting clock 194000 Hz, block size 512 mci: setting clock 194000 Hz, block size 512 mci: setting clock 24832000 Hz, block size 512 98304 blocks written: OK TOP9000> Reinhard