Date: Thu, 5 Dec 2013 05:58:17 +0000 (UTC) From: Justin Hibbits <jhibbits@FreeBSD.org> To: src-committers@freebsd.org, svn-src-projects@freebsd.org Subject: svn commit: r258957 - projects/pmac_pmu/sys/powerpc/powermac Message-ID: <201312050558.rB55wHD3074193@svn.freebsd.org>
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Author: jhibbits Date: Thu Dec 5 05:58:17 2013 New Revision: 258957 URL: http://svnweb.freebsd.org/changeset/base/258957 Log: Fix the cache flushing code, by flushing the L1 twice. Linux and OS X do this very thing, possibly to work around bugs in the silicon. Without this it doesn't flush completely, and results in memory corruption down the road. Modified: projects/pmac_pmu/sys/powerpc/powermac/platform_powermac.c Modified: projects/pmac_pmu/sys/powerpc/powermac/platform_powermac.c ============================================================================== --- projects/pmac_pmu/sys/powerpc/powermac/platform_powermac.c Thu Dec 5 03:01:41 2013 (r258956) +++ projects/pmac_pmu/sys/powerpc/powermac/platform_powermac.c Thu Dec 5 05:58:17 2013 (r258957) @@ -332,7 +332,7 @@ flush_disable_caches(void) register_t msr; register_t msscr0; register_t cache_reg; - volatile uint32_t *romp; + volatile uint32_t *memp; uint32_t temp; int i; int x; @@ -359,17 +359,30 @@ flush_disable_caches(void) mtspr(SPR_LDSTCR, 0); - romp = (uint32_t *)0xfff00000; + /* + * Perform this in two stages: Flush the cache starting in RAM, then do it + * from ROM. + */ + memp = (volatile uint32_t *)0x00000000; + for (i = 0; i < 128 * 1024; i++) { + temp = *memp; + __asm__ __volatile__("dcbf 0,%0" :: "r"(memp)); + memp += 32/sizeof(*memp); + } + + memp = (volatile uint32_t *)0xfff00000; x = 0xfe; for (; x != 0xff;) { mtspr(SPR_LDSTCR, x); for (i = 0; i < 128; i++) { - temp = *romp; - romp += 32/sizeof(*romp); + temp = *memp; + __asm__ __volatile__("dcbf 0,%0" :: "r"(memp)); + memp += 32/sizeof(*memp); } x = ((x << 1) | 1) & 0xff; } + mtspr(SPR_LDSTCR, 0); cache_reg = mfspr(SPR_L2CR); if (cache_reg & L2CR_L2E) {
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