/** * struct omap_sdrc_params - SDRC parameters for a given SDRC clock rate * @rate: SDRC clock rate (in Hz) * @actim_ctrla: Value to program to SDRC_ACTIM_CTRLA for this rate * @actim_ctrlb: Value to program to SDRC_ACTIM_CTRLB for this rate * @rfr_ctrl: Value to program to SDRC_RFR_CTRL for this rate * @mr: Value to program to SDRC_MR for this rate * * This structure holds a pre-computed set of register values for the * SDRC for a given SDRC clock rate and SDRAM chip. These are * intended to be pre-computed and specified in an array in the board-*.c * files. The structure is keyed off the 'rate' field.
*/ struct omap_sdrc_params { unsignedlong rate;
u32 actim_ctrla;
u32 actim_ctrlb;
u32 rfr_ctrl;
u32 mr;
};
/* * These values represent the number of memory clock cycles between * autorefresh initiation. They assume 1 refresh per 64 ms (JEDEC), 8192 * rows per device, and include a subtraction of a 50 cycle window in the * event that the autorefresh command is delayed due to other SDRC activity. * The '| 1' sets the ARE field to send one autorefresh when the autorefresh * counter reaches 0. * * These represent optimal values for common parts, it won't work for all. * As long as you scale down, most parameters are still work, they just * become sub-optimal. The RFR value goes in the opposite direction. If you * don't adjust it down as your clock period increases the refresh interval * will not be met. Setting all parameters for complete worst case may work, * but may cut memory performance by 2x. Due to errata the DLLs need to be * unlocked and their value needs run time calibration. A dynamic call is * need for that as no single right value exists across production samples. * * Only the FULL speed values are given. Current code is such that rate * changes must be made at DPLLoutx2. The actual value adjustment for low * frequency operation will be handled by omap_set_performance() * * By having the boot loader boot up in the fastest L4 speed available likely * will result in something which you can switch between.
*/ #define SDRC_RFR_CTRL_165MHz (0x00044c00 | 1) #define SDRC_RFR_CTRL_133MHz (0x0003de00 | 1) #define SDRC_RFR_CTRL_100MHz (0x0002da01 | 1) #define SDRC_RFR_CTRL_110MHz (0x0002da01 | 1) /* Need to calc */ #define SDRC_RFR_CTRL_BYPASS (0x00005000 | 1) /* Need to calc */
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