linux-kernel - [PATCH 1/2] x86/CPU: Use correct macros for Cyrix calls on Geode processors

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Message-Id: <1552596361-8967-2-git-send-email-tedheadster@gmail.com>
Date:   Thu, 14 Mar 2019 16:46:00 -0400
From:   Matthew Whitehead <tedheadster@...il.com>
To:     linux-kernel@...r.kernel.org, tglx@...utronix.de, mingo@...nel.org,
        luto@...nel.org
Cc:     Matthew Whitehead <tedheadster@...il.com>
Subject: [PATCH 1/2] x86/CPU: Use correct macros for Cyrix calls on Geode processors

There are comments in processor-cyrix.h advising you to _not_ make calls
using the deprecated macros in this style:

  setCx86_old(CX86_CCR4, getCx86_old(CX86_CCR4) | 0x80);

This is because it expands the macro into a non-functioning calling
sequence. The calling order must be:

  outb(CX86_CCR2, 0x22);
  inb(0x23);

>From the comments:

 * When using the old macros a line like
 *   setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x88);
 * gets expanded to:
 *  do {
 *    outb((CX86_CCR2), 0x22);
 *    outb((({
 *        outb((CX86_CCR2), 0x22);
 *        inb(0x23);
 *    }) | 0x88), 0x23);
 *  } while (0);

The new macros fix this problem, so use them instead. Tested on an
actual Geode processor.

Signed-off-by: Matthew Whitehead <tedheadster@...il.com>
---
 arch/x86/kernel/cpu/cyrix.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kernel/cpu/cyrix.c b/arch/x86/kernel/cpu/cyrix.c
index d12226f..1d9b8aa 100644
--- a/arch/x86/kernel/cpu/cyrix.c
+++ b/arch/x86/kernel/cpu/cyrix.c
@@ -124,7 +124,7 @@ static void set_cx86_reorder(void)
 	setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10); /* enable MAPEN */
 
 	/* Load/Store Serialize to mem access disable (=reorder it) */
-	setCx86_old(CX86_PCR0, getCx86_old(CX86_PCR0) & ~0x80);
+	setCx86(CX86_PCR0, getCx86(CX86_PCR0) & ~0x80);
 	/* set load/store serialize from 1GB to 4GB */
 	ccr3 |= 0xe0;
 	setCx86(CX86_CCR3, ccr3);
@@ -135,11 +135,11 @@ static void set_cx86_memwb(void)
 	pr_info("Enable Memory-Write-back mode on Cyrix/NSC processor.\n");
 
 	/* CCR2 bit 2: unlock NW bit */
-	setCx86_old(CX86_CCR2, getCx86_old(CX86_CCR2) & ~0x04);
+	setCx86(CX86_CCR2, getCx86(CX86_CCR2) & ~0x04);
 	/* set 'Not Write-through' */
 	write_cr0(read_cr0() | X86_CR0_NW);
 	/* CCR2 bit 2: lock NW bit and set WT1 */
-	setCx86_old(CX86_CCR2, getCx86_old(CX86_CCR2) | 0x14);
+	setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x14);
 }
 
 /*
@@ -153,14 +153,14 @@ static void geode_configure(void)
 	local_irq_save(flags);
 
 	/* Suspend on halt power saving and enable #SUSP pin */
-	setCx86_old(CX86_CCR2, getCx86_old(CX86_CCR2) | 0x88);
+	setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x88);
 
 	ccr3 = getCx86(CX86_CCR3);
 	setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10);	/* enable MAPEN */
 
 
 	/* FPU fast, DTE cache, Mem bypass */
-	setCx86_old(CX86_CCR4, getCx86_old(CX86_CCR4) | 0x38);
+	setCx86(CX86_CCR4, getCx86(CX86_CCR4) | 0x38);
 	setCx86(CX86_CCR3, ccr3);			/* disable MAPEN */
 
 	set_cx86_memwb();
@@ -296,7 +296,7 @@ static void init_cyrix(struct cpuinfo_x86 *c)
 		/* GXm supports extended cpuid levels 'ala' AMD */
 		if (c->cpuid_level == 2) {
 			/* Enable cxMMX extensions (GX1 Datasheet 54) */
-			setCx86_old(CX86_CCR7, getCx86_old(CX86_CCR7) | 1);
+			setCx86(CX86_CCR7, getCx86(CX86_CCR7) | 1);
 
 			/*
 			 * GXm : 0x30 ... 0x5f GXm  datasheet 51
@@ -319,7 +319,7 @@ static void init_cyrix(struct cpuinfo_x86 *c)
 		if (dir1 > 7) {
 			dir0_msn++;  /* M II */
 			/* Enable MMX extensions (App note 108) */
-			setCx86_old(CX86_CCR7, getCx86_old(CX86_CCR7)|1);
+			setCx86(CX86_CCR7, getCx86(CX86_CCR7)|1);
 		} else {
 			/* A 6x86MX - it has the bug. */
 			set_cpu_bug(c, X86_BUG_COMA);
-- 
1.8.3.1