[RFC 17/17] clk: zynq: remove call to of_clk_init

Sören Brinkmann soren.brinkmann at xilinx.com
Thu Aug 22 20:26:47 EDT 2013


Hi Sebastian,

On Tue, Aug 20, 2013 at 04:04:31AM +0200, Sebastian Hesselbarth wrote:
> With arch/arm calling of_clk_init(NULL) from time_init(), we can now
> remove it from corresponding drivers/clk code.

I think that would break Zynq.
If I see this correctly you call of_clk_init() from common code,
_before_ the SOC specific time init function is called.
The problem is, that we have code setting up a global pointer which is
required by zynq_clk_setup() which is triggered when of_clk_init() is
called.

Let me try to illustrate the current call graph:

time_init()
	zynq_timer_init()		// this machines init_time()
		zynq_slcr_init()	// setup System Level Control Registers including a global pointer
			zynq_clock_init()
				of_clk_init()
					zynq_clk_setup()   // requires pointer setup in zynq_slcr_init()
					...

IIUC, your series would change this to:
time_init()
	of_clk_init()
		zynq_clk_setup()	// SLCR pointer is not setup/NULL
		...
	zynq_timer_init()
		zynq_slcr_init()	// now the pointer becomes valid

	Sören





More information about the linux-arm-kernel mailing list