Author: wmb Date: Thu Aug 11 02:46:27 2011 New Revision: 2458 URL: http://tracker.coreboot.org/trac/openfirmware/changeset/2458
Log: OLPC XO-1.75 - Added DRAM recalibration.
Added: cpu/arm/mmp2/dramrecal.fth Modified: cpu/arm/olpc/1.75/devices.fth
Added: cpu/arm/mmp2/dramrecal.fth ============================================================================== --- /dev/null 00:00:00 1970 (empty, because file is newly added) +++ cpu/arm/mmp2/dramrecal.fth Thu Aug 11 02:46:27 2011 (r2458) @@ -0,0 +1,98 @@ +\ See license at end of file +purpose: Recalibrate DDR3 DRAM + +\ This code must be executed from SRAM because it touches the DRAM memory controller +label ddr-recal ( r0: memctrl-va -- ) + mov r1, #0x80000000 \ PHY Sync Enable (WO) - Synchronize dclk2x and dclk in the PHY + str r1, [r0, #0x240] \ PHY_CTRL14 + + \ The value "f" for the reset timer is in units of 256 (memory clock?) cycles, thus + \ the timer is set to 256*15 + ldr r1, [r0, #0x230] + orr r1, r1, #0xf0000000 \ DLL Reset timer + str r1, [r0, #0x230] \ PHY_CTRL13 + + \ Block all Memory Controller accesses until the DLL Reset timer expires + mov r1, #0x20000000 \ PHY DLL Reset (WO) + str r1, [r0, #0x240] \ PHY_CTRL14 + + mov r1, #0x40000000 \ DLL Update enable + str r1, [r0, #0x240] \ PHY_CTRL14 + + mov r1, #0x80 \ Exit self-refresh + str r1, [r0, #0x120] \ USER_INITIATED_COMMAND0 + + ldr r1, [r0, #0x80] \ SDRAM_CTRL1 + orr r1, r1, #0x40 \ DLL_RESET + str r1, [r0, #0x80] \ SDRAM_CTRL1 + + mov r1, #0x01000000 \ Chip select 0 + orr r1, r1, #0x00000100 \ Initiate Mode Register Set + str r1, [r0, #0x120] \ USER_INITIATED_COMMAND0 + + mov r1, #0x01000000 \ Chip select 0 + orr r1, r1, #0x00001000 \ Initiate ZQ calibration long + str r1, [r0, #0x120] \ USER_INITIATED_COMMAND0 + + \ ZQ calibration long takes 512 memory clock cycles after a reset + \ At 400 MHz, that's a little more than 2 us. We spin here to + \ ensure that the recal is complete before we touch the DRAM again. + mov r1, #0x100000 \ 512K spins, takes about 2.6 us + begin + decs r1, #1 + 0= until + + mov r1, #0x0 \ Normal operation (unblock data requests) + str r1, [r0, #0x7e0] \ SDRAM_CTRL14 + + mov pc,lr +end-code +here ddr-recal - constant /ddr-recal + +h# d000.0000 constant memctrl-pa +h# d000.0000 constant memctrl-va +h# d100.0000 constant sram-pa +h# d100.0000 constant sram-va +sram-va h# 2.0000 + constant 'ddr-recal + +: ddr-recal-to-sram ( -- ) + memctrl-pa h# c02 or memctrl-va map-section \ Map the memory controller + sram-pa h# c0e or sram-va map-section \ Make the code cacheable + ddr-recal 'ddr-recal /ddr-recal move +; + +stand-init: Setup DDR3 recalibration + ddr-recal-to-sram +; + +\ Call this from OFW to perform a recalibration +code do-recal ( -- ) + set r0,`memctrl-va #` \ Memory controller virtual address + set r1,`'ddr-recal #` \ Address of ddr-recal routine in SRAM + mov lr,pc + mov pc,r1 +c; + +\ LICENSE_BEGIN +\ Copyright (c) 2011 FirmWorks +\ +\ Permission is hereby granted, free of charge, to any person obtaining +\ a copy of this software and associated documentation files (the +\ "Software"), to deal in the Software without restriction, including +\ without limitation the rights to use, copy, modify, merge, publish, +\ distribute, sublicense, and/or sell copies of the Software, and to +\ permit persons to whom the Software is furnished to do so, subject to +\ the following conditions: +\ +\ The above copyright notice and this permission notice shall be +\ included in all copies or substantial portions of the Software. +\ +\ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, +\ EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF +\ MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND +\ NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE +\ LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION +\ OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION +\ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. +\ +\ LICENSE_END
Modified: cpu/arm/olpc/1.75/devices.fth ============================================================================== --- cpu/arm/olpc/1.75/devices.fth Wed Aug 10 02:57:09 2011 (r2457) +++ cpu/arm/olpc/1.75/devices.fth Thu Aug 11 02:46:27 2011 (r2458) @@ -390,6 +390,8 @@
fload ${BP}/cpu/arm/mmp2/thermal.fth
+fload ${BP}/cpu/arm/mmp2/dramrecal.fth + \ LICENSE_BEGIN \ Copyright (c) 2010 FirmWorks \