]> git.kernelconcepts.de Git - karo-tx-uboot.git/commitdiff
arm: socfpga: Fix delay in freeze controller
authorMarek Vasut <marex@denx.de>
Mon, 10 Aug 2015 22:49:09 +0000 (00:49 +0200)
committerLothar Waßmann <LW@KARO-electronics.de>
Thu, 10 Sep 2015 08:30:34 +0000 (10:30 +0200)
Based on observation, this udelay(20) was apparently too high and caused
subsequent failure to calibrate DDR when U-Boot was compiled with certain
toolchains. Lowering this delay fixed the problem.

Instead of permanently lowering the delay, calculate the correct delay
based on the original comment, that is, obtain EOSC1 frequency and use
it to calculate the precise delay.

Signed-off-by: Marek Vasut <marex@denx.de>
arch/arm/mach-socfpga/freeze_controller.c

index 0be643c817971fce5d7bbc68f0460420cfdecae7..2b1679555490af094c5808c5c4440fbc44697f82 100644 (file)
@@ -7,8 +7,8 @@
 
 #include <common.h>
 #include <asm/io.h>
+#include <asm/arch/clock_manager.h>
 #include <asm/arch/freeze_controller.h>
-#include <asm/arch/timer.h>
 #include <asm/errno.h>
 
 DECLARE_GLOBAL_DATA_PTR;
@@ -112,6 +112,7 @@ void sys_mgr_frzctrl_thaw_req(void)
        u32 reg_cfg_mask;
        u32 reg_value;
        u32 channel_id;
+       unsigned long eosc1_freq;
 
        /* select software FSM */
        writel(SYSMGR_FRZCTRL_SRC_VIO1_ENUM_SW, &freeze_controller_base->src);
@@ -162,12 +163,9 @@ void sys_mgr_frzctrl_thaw_req(void)
        setbits_le32(&freeze_controller_base->hioctrl,
                SYSMGR_FRZCTRL_HIOCTRL_OCT_CFGEN_CALSTART_MASK);
 
-       /*
-        * Delay 1000 intosc. intosc is based on eosc1
-        * Use worst case which is fatest eosc1=50MHz, delay required
-        * is 1/50MHz * 1000 = 20us
-        */
-       udelay(20);
+       /* Delay 1000 intosc cycles. The intosc is based on eosc1. */
+       eosc1_freq = cm_get_osc_clk_hz(1) / 1000;       /* kHz */
+       udelay(DIV_ROUND_UP(1000000, eosc1_freq));
 
        /*
         * de-assert active low bhniotri signals,