u-boot/arch/arm/mach-imx/mmdc_size.c
Fabio Estevam 89bc388a32 imx: Place imx_ddr_size() into a separate file
Place imx_ddr_size() into a separate file.

The motivation for doing this is to be able to easily reuse
imx_ddr_size() on i.MX7ULP.

Currently imx_ddr_size() is inside arch/arm/mach-imx/cpu.c, which
is not built for i.MX7ULP.

Changing the logic to allow building cpu.c for i.MX7UP would
require adding several ifdef's, leading to a not a very elegant
solution.

To allow better reuse, just place imx_ddr_size() into a common
mmdc_size.c file.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Stefano Babic <sbabic@denx.de>
2019-10-14 09:31:33 +02:00

55 lines
1.6 KiB
C

// SPDX-License-Identifier: GPL-2.0+
#include <common.h>
#include <asm/io.h>
#if defined(CONFIG_MX53)
#define MEMCTL_BASE ESDCTL_BASE_ADDR
#else
#define MEMCTL_BASE MMDC_P0_BASE_ADDR
#endif
static const unsigned char col_lookup[] = {9, 10, 11, 8, 12, 9, 9, 9};
static const unsigned char bank_lookup[] = {3, 2};
/* these MMDC registers are common to the IMX53 and IMX6 */
struct esd_mmdc_regs {
uint32_t ctl;
uint32_t pdc;
uint32_t otc;
uint32_t cfg0;
uint32_t cfg1;
uint32_t cfg2;
uint32_t misc;
};
#define ESD_MMDC_CTL_GET_ROW(mdctl) ((ctl >> 24) & 7)
#define ESD_MMDC_CTL_GET_COLUMN(mdctl) ((ctl >> 20) & 7)
#define ESD_MMDC_CTL_GET_WIDTH(mdctl) ((ctl >> 16) & 3)
#define ESD_MMDC_CTL_GET_CS1(mdctl) ((ctl >> 30) & 1)
#define ESD_MMDC_MISC_GET_BANK(mdmisc) ((misc >> 5) & 1)
/*
* imx_ddr_size - return size in bytes of DRAM according MMDC config
* The MMDC MDCTL register holds the number of bits for row, col, and data
* width and the MMDC MDMISC register holds the number of banks. Combine
* all these bits to determine the meme size the MMDC has been configured for
*/
unsigned imx_ddr_size(void)
{
struct esd_mmdc_regs *mem = (struct esd_mmdc_regs *)MEMCTL_BASE;
unsigned ctl = readl(&mem->ctl);
unsigned misc = readl(&mem->misc);
int bits = 11 + 0 + 0 + 1; /* row + col + bank + width */
bits += ESD_MMDC_CTL_GET_ROW(ctl);
bits += col_lookup[ESD_MMDC_CTL_GET_COLUMN(ctl)];
bits += bank_lookup[ESD_MMDC_MISC_GET_BANK(misc)];
bits += ESD_MMDC_CTL_GET_WIDTH(ctl);
bits += ESD_MMDC_CTL_GET_CS1(ctl);
/* The MX6 can do only 3840 MiB of DRAM */
if (bits == 32)
return 0xf0000000;
return 1 << bits;
}