On Friday, February 11, 2011 11:01:40 pm Albert ARIBAUD wrote: > Le 12/02/2011 07:42, Aaron Williams a écrit : > > I've placed the results of the scan below. > > > > The problem is that in 8-bit mode the code that scans the CFI does not > > follow the specification. > > > > In the specification to read the CFI data you write 0x98 to address 0xAA, > > not address 0x55 as you do in 16-bit mode. flash_offset_cfi is set to > > 0x55 which in this case is wrong and won't work. When it tries 16-bit > > mode then it writes to address 0xAA which causes it to work. > > Let us see the specs, then. The specs I have (admittedly not necessarily > the latest: I use JESD 68.01, september 1999) state the following: > > "Nonvolatile memory devices are assumed to power up in a read-only > state. Independent of that assumption, the Query structure contents must > be able to be read at the specific address locations following a single > system write cycle where: 1) a 98h Query command code is written to 55h > address location within the device’s address space (in maximum device > buswidth), and 2) the device is in any valid read state, such as “Read > Array” or “Read ID Data”. > > I read "55h address location within the device’s address space (in > maximum device buswidth" as implying that 0x55 is the only address to > use but is in device bus terms, and that may mean different CPU > addresses for different devices types: for x8 devices, one should access > the byte address 0x55 because the device bus is in bytes, whereas for > x8/x16 and x16 devices, one should access byte address 0xAA because it > translates to x16 device bus address 0x55 -- regardless of actual x8 or > x16 mode. > > Are we in sync here? > > Now it's been a long time since I last looked at my ED Mini V2 Flash, > but I should be able to dig it up and do a test within one or two hours. > > > -Aaron > > > Here's the results of the scan: > Yes, that's what U-boot *CFI code* does, but I'd like to see what very > basic writes and reads give without any detection logic involved. > > Amicalement,
I'm looking at the Spansion S29GL-N datasheet from 2008. Look at table 10.3 on page 53. http://www.spansion.com/Support/Datasheets/S29GL-N_01_12_e.pdf -Aaron _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
