From:   Sasha Levin <sashal@kernel.org>
To:     linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc:     Alexey Kardashevskiy <aik@ozlabs.ru>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Sasha Levin <sashal@kernel.org>, leobras.c@gmail.com,
        fbarrat@linux.ibm.com, linuxppc-dev@lists.ozlabs.org
Subject: [PATCH AUTOSEL 5.15 03/39] powerpc/pseries/ddw: Revert "Extend upper limit for huge DMA window for persistent memory"
Date:   Thu, 25 Nov 2021 21:31:20 -0500
Message-Id: <20211126023156.441292-3-sashal@kernel.org>
In-Reply-To: <20211126023156.441292-1-sashal@kernel.org>
References: <20211126023156.441292-1-sashal@kernel.org>
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From: Alexey Kardashevskiy <aik@ozlabs.ru>

[ Upstream commit 2d33f5504490a9d90924476dbccd4a5349ee1ad0 ]

This reverts commit 54fc3c681ded9437e4548e2501dc1136b23cfa9a
which does not allow 1:1 mapping even for the system RAM which
is usually possible.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211108040320.3857636-2-aik@ozlabs.ru
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/powerpc/platforms/pseries/iommu.c | 9 ---------
 1 file changed, 9 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c
index a52af8fbf5711..ad96d6e13d1f6 100644
--- a/arch/powerpc/platforms/pseries/iommu.c
+++ b/arch/powerpc/platforms/pseries/iommu.c
@@ -1092,15 +1092,6 @@ static phys_addr_t ddw_memory_hotplug_max(void)
 	phys_addr_t max_addr = memory_hotplug_max();
 	struct device_node *memory;
 
-	/*
-	 * The "ibm,pmemory" can appear anywhere in the address space.
-	 * Assuming it is still backed by page structs, set the upper limit
-	 * for the huge DMA window as MAX_PHYSMEM_BITS.
-	 */
-	if (of_find_node_by_type(NULL, "ibm,pmemory"))
-		return (sizeof(phys_addr_t) * 8 <= MAX_PHYSMEM_BITS) ?
-			(phys_addr_t) -1 : (1ULL << MAX_PHYSMEM_BITS);
-
 	for_each_node_by_type(memory, "memory") {
 		unsigned long start, size;
 		int n_mem_addr_cells, n_mem_size_cells, len;
-- 
2.33.0