linux-kernel - [PATCH] MIPS: Malta: Cleanup DMA coherence #ifdefs

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Date:   Fri, 2 Sep 2016 16:10:06 +0100
From:   Paul Burton <paul.burton@...tec.com>
To:     <linux-mips@...ux-mips.org>
CC:     Paul Burton <paul.burton@...tec.com>,
        Matt Redfearn <matt.redfearn@...tec.com>,
        Masahiro Yamada <yamada.masahiro@...ionext.com>,
        Kees Cook <keescook@...omium.org>,
        <linux-kernel@...r.kernel.org>, Ralf Baechle <ralf@...ux-mips.org>,
        Andrew Morton <akpm@...ux-foundation.org>
Subject: [PATCH] MIPS: Malta: Cleanup DMA coherence #ifdefs

DMA coherence is not user-selectable in Kconfig, and Malta selects
CONFIG_DMA_MAYBE_COHERENT which in turn selects CONFIG_DMA_NONCOHERENT.
Remove #ifdefs on CONFIG_DMA_COHERENT which is not set for Malta. This
removes a significant amount of code from bonito_quirks_setup(), but the
code is duplicated in plat_enable_iocoherency() anyway so we lose
nothing but duplication.

Signed-off-by: Paul Burton <paul.burton@...tec.com>
---

 arch/mips/mti-malta/malta-setup.c | 38 --------------------------------------
 1 file changed, 38 deletions(-)

diff --git a/arch/mips/mti-malta/malta-setup.c b/arch/mips/mti-malta/malta-setup.c
index ec5b216..e573402 100644
--- a/arch/mips/mti-malta/malta-setup.c
+++ b/arch/mips/mti-malta/malta-setup.c
@@ -141,12 +141,6 @@ static int __init plat_enable_iocoherency(void)
 
 static void __init plat_setup_iocoherency(void)
 {
-#ifdef CONFIG_DMA_NONCOHERENT
-	/*
-	 * Kernel has been configured with software coherency
-	 * but we might choose to turn it off and use hardware
-	 * coherency instead.
-	 */
 	if (plat_enable_iocoherency()) {
 		if (coherentio == 0)
 			pr_info("Hardware DMA cache coherency disabled\n");
@@ -158,10 +152,6 @@ static void __init plat_setup_iocoherency(void)
 		else
 			pr_info("Software DMA cache coherency enabled\n");
 	}
-#else
-	if (!plat_enable_iocoherency())
-		panic("Hardware DMA cache coherency not supported!");
-#endif
 }
 
 static void __init pci_clock_check(void)
@@ -223,29 +213,6 @@ static void __init bonito_quirks_setup(void)
 		pr_info("Enabled Bonito debug mode\n");
 	} else
 		BONITO_BONGENCFG &= ~BONITO_BONGENCFG_DEBUGMODE;
-
-#ifdef CONFIG_DMA_COHERENT
-	if (BONITO_PCICACHECTRL & BONITO_PCICACHECTRL_CPUCOH_PRES) {
-		BONITO_PCICACHECTRL |= BONITO_PCICACHECTRL_CPUCOH_EN;
-		pr_info("Enabled Bonito CPU coherency\n");
-
-		argptr = fw_getcmdline();
-		if (strstr(argptr, "iobcuncached")) {
-			BONITO_PCICACHECTRL &= ~BONITO_PCICACHECTRL_IOBCCOH_EN;
-			BONITO_PCIMEMBASECFG = BONITO_PCIMEMBASECFG &
-				~(BONITO_PCIMEMBASECFG_MEMBASE0_CACHED |
-					BONITO_PCIMEMBASECFG_MEMBASE1_CACHED);
-			pr_info("Disabled Bonito IOBC coherency\n");
-		} else {
-			BONITO_PCICACHECTRL |= BONITO_PCICACHECTRL_IOBCCOH_EN;
-			BONITO_PCIMEMBASECFG |=
-				(BONITO_PCIMEMBASECFG_MEMBASE0_CACHED |
-					BONITO_PCIMEMBASECFG_MEMBASE1_CACHED);
-			pr_info("Enabled Bonito IOBC coherency\n");
-		}
-	} else
-		panic("Hardware DMA cache coherency not supported");
-#endif
 }
 
 void __init *plat_get_fdt(void)
@@ -276,11 +243,6 @@ void __init plat_mem_setup(void)
 	 */
 	enable_dma(4);
 
-#ifdef CONFIG_DMA_COHERENT
-	if (mips_revision_sconid != MIPS_REVISION_SCON_BONITO)
-		panic("Hardware DMA cache coherency not supported");
-#endif
-
 	if (mips_revision_sconid == MIPS_REVISION_SCON_BONITO)
 		bonito_quirks_setup();
 
-- 
2.9.3