[U-Boot-Users] Clock settings - just can't figure it out.

p pmeloy at shaw.ca
Sun May 4 17:38:29 CEST 2008


Sorry to be a pest but I just can't figure out how to set the CPU
properly in u-boot for my s3c2410. I think I have the first part correct
for 266mHz but I get usb and other problems when booting the kernel. If
I use the s3c24xx speed set 266 (openmoko patch) then things work
flawlessly.

This is what I'm trying for
FCLK = 266 MHz, HCLK = 133 MHz, PCLK = 66 MHz, UCLK = 48 MHz

The relvent sections of cmd_s3cxx.c from the openmoko patch show

#define CLKDIVN_1_2_4	0x03

static const u_int32_t upllcon = ((0x78 << 12) + (0x2 << 4) + 0x3);

static const struct s3c24x0_pll_speed pll_configs[] = {
	... (omitted other speeds)
	{
		.mhz = 266,
		.mpllcon = ((0x7d << 12) + (0x1 << 4) + 0x1),
		.clkdivn = CLKDIVN_1_2_4,
	},
};



Here's what I have in the u-Boot board config so far

#define M_MDIV 0x7d 
#define M_PDIV 0x1
#define M_SDIV 0x1

#define U_M_MDIV 0x78
#define U_M_PDIV 0x2
#define U_M_SDIV 0x3

I know I stumbled across a clock calculator for the s3c2410 somewhere on
the net but of course now I can't find it anywhere.

Thanks for any help you can render. This is the last thing I need to be
able to complete my u-boot setup.







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