linux-kernel - [PATCH 8/8] ARM: at91: pm: do not disable/enable PLLA for ULP modes

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 14 Feb 2019 15:55:06 +0000
From:   <Claudiu.Beznea@...rochip.com>
To:     <robh+dt@...nel.org>, <mark.rutland@....com>,
        <Nicolas.Ferre@...rochip.com>, <alexandre.belloni@...tlin.com>,
        <Ludovic.Desroches@...rochip.com>, <linux@...linux.org.uk>,
        <mturquette@...libre.com>, <sboyd@...nel.org>
CC:     <devicetree@...r.kernel.org>,
        <linux-arm-kernel@...ts.infradead.org>,
        <linux-kernel@...r.kernel.org>, <linux-clk@...r.kernel.org>,
        <Claudiu.Beznea@...rochip.com>
Subject: [PATCH 8/8] ARM: at91: pm: do not disable/enable PLLA for ULP modes

From: Claudiu Beznea <claudiu.beznea@...rochip.com>

There is no need to disable/enable PLLA when switching to one of the
ULP modes. The PLLA consumers should take care of this.

Signed-off-by: Claudiu Beznea <claudiu.beznea@...rochip.com>
---
 arch/arm/mach-at91/pm_suspend.S | 31 -------------------------------
 1 file changed, 31 deletions(-)

diff --git a/arch/arm/mach-at91/pm_suspend.S b/arch/arm/mach-at91/pm_suspend.S
index 5c33023f9129..77e29309cc6e 100644
--- a/arch/arm/mach-at91/pm_suspend.S
+++ b/arch/arm/mach-at91/pm_suspend.S
@@ -51,15 +51,6 @@ tmp2	.req	r5
 	.endm
 
 /*
- * Wait until PLLA has locked.
- */
-	.macro wait_pllalock
-1:	ldr	tmp1, [pmc, #AT91_PMC_SR]
-	tst	tmp1, #AT91_PMC_LOCKA
-	beq	1b
-	.endm
-
-/*
  * Put the processor to enter the idle state
  */
 	.macro at91_cpu_idle
@@ -351,14 +342,6 @@ ENTRY(at91_ulp_mode)
 
 	wait_mckrdy
 
-	/* Save PLLA setting and disable it */
-	ldr	tmp1, [pmc, #AT91_CKGR_PLLAR]
-	str	tmp1, .saved_pllar
-
-	mov	tmp1, #AT91_PMC_PLLCOUNT
-	orr	tmp1, tmp1, #(1 << 29)		/* bit 29 always set */
-	str	tmp1, [pmc, #AT91_CKGR_PLLAR]
-
 	ldr	r0, .pm_mode
 	cmp	r0, #AT91_PM_ULP1
 	beq	ulp1_mode
@@ -373,18 +356,6 @@ ulp1_mode:
 ulp_exit:
 	ldr	pmc, .pmc_base
 
-	/* Restore PLLA setting */
-	ldr	tmp1, .saved_pllar
-	str	tmp1, [pmc, #AT91_CKGR_PLLAR]
-
-	tst	tmp1, #(AT91_PMC_MUL &  0xff0000)
-	bne	3f
-	tst	tmp1, #(AT91_PMC_MUL & ~0xff0000)
-	beq	4f
-3:
-	wait_pllalock
-4:
-
 	/*
 	 * Restore master clock setting
 	 */
@@ -537,8 +508,6 @@ ENDPROC(at91_sramc_self_refresh)
 	.word 0
 .saved_mckr:
 	.word 0
-.saved_pllar:
-	.word 0
 .saved_sam9_lpr:
 	.word 0
 .saved_sam9_lpr1:
-- 
2.7.4