From nobody Fri Feb 13 11:10:52 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 36510CE7AB9 for ; Mon, 25 Sep 2023 18:06:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232165AbjIYSG2 (ORCPT ); Mon, 25 Sep 2023 14:06:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35650 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229584AbjIYSG0 (ORCPT ); Mon, 25 Sep 2023 14:06:26 -0400 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 7E4C210C; Mon, 25 Sep 2023 11:06:17 -0700 (PDT) Received: from localhost.localdomain (unknown [167.220.81.210]) by linux.microsoft.com (Postfix) with ESMTPSA id C1BC1212C816; Mon, 25 Sep 2023 11:06:16 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com C1BC1212C816 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1695665176; bh=p14Nn8yShFD3PfmnLpi1+w5sDpk1yljf0ug3OMUAn1A=; h=From:To:Subject:Date:From; b=aYiDuMSiNfoqP1ABMbBcdZ++MtF6+932VxIdLt8NPUWFwI0NqurbgHc0dOFr6h1nz vjeT21O0jYE2Agwul0i8dRPtNgd3O8wC/xO0I6GG6gnJ5BQX5rllfGvZesNZwHqG43 yH7M126uFcTaVUIciQeaIsPaSHpW7y+pfFksFMFs= From: Jarred White To: "Rafael J. Wysocki" , Len Brown , linux-acpi@vger.kernel.org (open list:ACPI), linux-kernel@vger.kernel.org (open list) Subject: [PATCH] acpi: Use access_width over register_width for system memory accesses Date: Mon, 25 Sep 2023 11:05:52 -0700 Message-Id: <20230925180552.76071-1-jarredwhite@linux.microsoft.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" To align with ACPI 6.3+, since bit_width can be any 8-bit value, we cannot depend on it being always on a clean 8b boundary. Instead, use access_width to determine the size and use the offset and width to shift and mask the bit swe want to read/write out. Make sure to add a check for system memory since pcc redefines the access_width to subspace id. Signed-off-by: Jarred White --- drivers/acpi/cppc_acpi.c | 24 +++++++++++++++++++++--- 1 file changed, 21 insertions(+), 3 deletions(-) diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index 7ff269a78c20..07619b36c056 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c @@ -777,6 +777,7 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr) } else if (gas_t->space_id =3D=3D ACPI_ADR_SPACE_SYSTEM_MEMORY) { if (gas_t->address) { void __iomem *addr; + size_t access_width; =20 if (!osc_cpc_flexible_adr_space_confirmed) { pr_debug("Flexible address space capability not supported\n"); @@ -784,7 +785,8 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr) goto out_free; } =20 - addr =3D ioremap(gas_t->address, gas_t->bit_width/8); + access_width =3D ((8 << (gas_t->access_width - 1)) / 8); + addr =3D ioremap(gas_t->address, access_width); if (!addr) goto out_free; cpc_ptr->cpc_regs[i-2].sys_mem_vaddr =3D addr; @@ -980,6 +982,7 @@ int __weak cpc_write_ffh(int cpunum, struct cpc_reg *re= g, u64 val) static int cpc_read(int cpu, struct cpc_register_resource *reg_res, u64 *v= al) { void __iomem *vaddr =3D NULL; + int size; int pcc_ss_id =3D per_cpu(cpu_pcc_subspace_idx, cpu); struct cpc_reg *reg =3D ®_res->cpc_entry.reg; =20 @@ -1015,7 +1018,12 @@ static int cpc_read(int cpu, struct cpc_register_res= ource *reg_res, u64 *val) return acpi_os_read_memory((acpi_physical_address)reg->address, val, reg->bit_width); =20 - switch (reg->bit_width) { + if (reg->space_id =3D=3D ACPI_ADR_SPACE_SYSTEM_MEMORY) + size =3D (8 << (reg->access_width - 1)); + else + size =3D reg->bit_width; + + switch (size) { case 8: *val =3D readb_relaxed(vaddr); break; @@ -1034,12 +1042,16 @@ static int cpc_read(int cpu, struct cpc_register_re= source *reg_res, u64 *val) return -EFAULT; } =20 + if (reg->space_id =3D=3D ACPI_ADR_SPACE_SYSTEM_MEMORY) + *val =3D (*val >> reg->bit_offset) & GENMASK((reg->bit_width) - 1, 0); + return 0; } =20 static int cpc_write(int cpu, struct cpc_register_resource *reg_res, u64 v= al) { int ret_val =3D 0; + int size; void __iomem *vaddr =3D NULL; int pcc_ss_id =3D per_cpu(cpu_pcc_subspace_idx, cpu); struct cpc_reg *reg =3D ®_res->cpc_entry.reg; @@ -1067,7 +1079,13 @@ static int cpc_write(int cpu, struct cpc_register_re= source *reg_res, u64 val) return acpi_os_write_memory((acpi_physical_address)reg->address, val, reg->bit_width); =20 - switch (reg->bit_width) { + if (reg->space_id =3D=3D ACPI_ADR_SPACE_SYSTEM_MEMORY) { + size =3D (8 << (reg->access_width - 1)); + val =3D (val >> reg->bit_offset) & GENMASK((reg->bit_width) - 1, 0); + } else + size =3D reg->bit_width; + + switch (size) { case 8: writeb_relaxed(val, vaddr); break; --=20 2.34.1