[PATCH v2] ARM: OMAP1: Update dpll1 default rate reprogramming method
Janusz Krzysztofik
jkrzyszt at tis.icnet.pl
Thu Dec 1 16:16:26 EST 2011
According to comments in omap1_select_table_rate(), reprogramming dpll1
is tricky, and should always be done from SRAM.
While being at it, move OMAP730 special case handling inside
omap_sram_reprogram_clock().
Created on top of version 2 of the series "ARM: OMAP1: Fix dpll1
reprogramming related issues", which it depends on.
Tested on Amstrad Delta.
Signed-off-by: Janusz Krzysztofik <jkrzyszt at tis.icnet.pl>
---
v2 changes:
* was 1/5, now separated with the intention of being deferred until next
merge window, and refreshed on top of that series,
* Fix replaced with Update in the summary.
arch/arm/mach-omap1/clock.c | 6 +-----
arch/arm/mach-omap1/clock_data.c | 7 +++++--
arch/arm/plat-omap/sram.c | 3 +++
3 files changed, 9 insertions(+), 7 deletions(-)
diff --git a/arch/arm/mach-omap1/clock.c b/arch/arm/mach-omap1/clock.c
index 84ef704..3899176 100644
--- a/arch/arm/mach-omap1/clock.c
+++ b/arch/arm/mach-omap1/clock.c
@@ -215,12 +215,8 @@ int omap1_select_table_rate(struct clk *clk, unsigned long rate)
/*
* In most cases we should not need to reprogram DPLL.
* Reprogramming the DPLL is tricky, it must be done from SRAM.
- * (on 730, bit 13 must always be 1)
*/
- if (cpu_is_omap7xx())
- omap_sram_reprogram_clock(ptr->dpllctl_val, ptr->ckctl_val | 0x2000);
- else
- omap_sram_reprogram_clock(ptr->dpllctl_val, ptr->ckctl_val);
+ omap_sram_reprogram_clock(ptr->dpllctl_val, ptr->ckctl_val);
/* XXX Do we need to recalculate the tree below DPLL1 at this point? */
ck_dpll1_p->rate = ptr->pll_rate;
diff --git a/arch/arm/mach-omap1/clock_data.c b/arch/arm/mach-omap1/clock_data.c
index 0ef1e7d..e616042 100644
--- a/arch/arm/mach-omap1/clock_data.c
+++ b/arch/arm/mach-omap1/clock_data.c
@@ -25,6 +25,7 @@
#include <plat/clock.h>
#include <plat/cpu.h>
#include <plat/clkdev_omap.h>
+#include <plat/sram.h> /* for omap_sram_reprogram_clock() */
#include <plat/usb.h> /* for OTG_BASE */
#include "clock.h"
@@ -937,8 +938,10 @@ void __init omap1_clk_late_init(void)
/* Find the highest supported frequency and enable it */
if (omap1_select_table_rate(&virtual_ck_mpu, ~0)) {
pr_err("System frequencies not set, using default. Check your config.\n");
- omap_writew(0x2290, DPLL_CTL);
- omap_writew(cpu_is_omap7xx() ? 0x2005 : 0x0005, ARM_CKCTL);
+ /*
+ * Reprogramming the DPLL is tricky, it must be done from SRAM.
+ */
+ omap_sram_reprogram_clock(0x2290, 0x0005);
ck_dpll1.rate = OMAP1_DPLL1_SANE_VALUE;
}
propagate_rate(&ck_dpll1);
diff --git a/arch/arm/plat-omap/sram.c b/arch/arm/plat-omap/sram.c
index 8b28664..312bee8 100644
--- a/arch/arm/plat-omap/sram.c
+++ b/arch/arm/plat-omap/sram.c
@@ -224,6 +224,9 @@ static void (*_omap_sram_reprogram_clock)(u32 dpllctl, u32 ckctl);
void omap_sram_reprogram_clock(u32 dpllctl, u32 ckctl)
{
BUG_ON(!_omap_sram_reprogram_clock);
+ /* On 730, bit 13 must always be 1 */
+ if (cpu_is_omap7xx())
+ ckctl |= 0x2000;
_omap_sram_reprogram_clock(dpllctl, ckctl);
}
--
1.7.3.4
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