Date: Thu, 05 Feb 2026 03:43:35 +0000 From: Justin Hibbits <jhibbits@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org Subject: git: c1a339b4a313 - main - powerpc64/pmap: No need to use r0 anymore in tlbie Message-ID: <698411e7.44bb3.7b40fde6@gitrepo.freebsd.org>
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The branch main has been updated by jhibbits: URL: https://cgit.FreeBSD.org/src/commit/?id=c1a339b4a313ead4122c630ab9ac8f9c54c3e0a2 commit c1a339b4a313ead4122c630ab9ac8f9c54c3e0a2 Author: Justin Hibbits <jhibbits@FreeBSD.org> AuthorDate: 2026-02-05 03:28:16 +0000 Commit: Justin Hibbits <jhibbits@FreeBSD.org> CommitDate: 2026-02-05 03:42:23 +0000 powerpc64/pmap: No need to use r0 anymore in tlbie The only use of `tlbie %rN, 0` is now explicit and covered in the block above. Since there's no need for an explicit `tlbie %rN, 0` now, drop this convoluted piece and let the compiler decide. While here, a trivial optimization of the old-style tlbie block, by clearing tlbie_lock and returning, instead of going to the end which checks again if the lock is needed. Since it's already known to be needed, there's no need to check again. --- sys/powerpc/aim/moea64_native.c | 17 +++-------------- 1 file changed, 3 insertions(+), 14 deletions(-) diff --git a/sys/powerpc/aim/moea64_native.c b/sys/powerpc/aim/moea64_native.c index 0ea44b1097b6..7714187c2f4d 100644 --- a/sys/powerpc/aim/moea64_native.c +++ b/sys/powerpc/aim/moea64_native.c @@ -183,7 +183,8 @@ TLBIE(uint64_t vpn, uint64_t oldptehi) "memory"); __asm __volatile("eieio; tlbsync; ptesync" ::: "memory"); - goto done; + tlbie_lock = 0; + return; #endif } } @@ -197,20 +198,8 @@ TLBIE(uint64_t vpn, uint64_t oldptehi) (oldptehi & LPTE_KERNEL_VSID_BIT) == 0) vpn |= AP_16M; - /* - * Explicitly clobber r0. The tlbie instruction has two forms: an old - * one used by PowerISA 2.03 and prior, and a newer one used by PowerISA - * 2.06 (maybe 2.05?) and later. We need to support both, and it just - * so happens that since we use 4k pages we can simply zero out r0, and - * clobber it, and the assembler will interpret the single-operand form - * of tlbie as having RB set, and everything else as 0. The RS operand - * in the newer form is in the same position as the L(page size) bit of - * the old form, so a slong as RS is 0, we're good on both sides. - */ - __asm __volatile("li 0, 0 \n tlbie %0, 0" :: "r"(vpn) : "r0", "memory"); + __asm __volatile("tlbie %0, %1" :: "r"(vpn), "r"(0) : "memory"); __asm __volatile("eieio; tlbsync; ptesync" ::: "memory"); -done: - #else vpn_hi = (uint32_t)(vpn >> 32); vpn_lo = (uint32_t)vpn;home | help
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