From patchwork Thu Jun 6 09:42:38 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lorenzo Pieralisi X-Patchwork-Id: 802036 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 076B515E5C9; Thu, 6 Jun 2024 09:42:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717666969; cv=none; b=rXLERFj6u/5X3AEqWbtQTt2l7XZV8K+VLdRNGV/a0XZHhb2zabl/Y6iq2LrdSkknYqUTGS7X6J8B4Fx5e2oGGOtCURCoUjvjPv3IWo6esT0BTV1V9i2hFUceZFWpZvNR6RMKP0hi4zjOyL/o9B5U9TstJmhUug9YzanZ+x1aFZE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717666969; c=relaxed/simple; bh=rYDwo9sVsMIRRs3ihHMD2TPD1n36mAZ6UOjA9MgTFl0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=eQI70CXNFqpEA0g0nv9yPWdgSWmtnNTLoKcyme8uivuF0O0WKnhUGtAHmX++H72a/tIQE9Xv9HIkClKS/nLRj5vqYonXld9pyOyLTG+pvV2IFEgG0mqbEgOvA9uMvhOELv0e5ve9I5mZN+dK90l9G1IL75rD5N2C8hXCfyfyyuc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=G2TkRhkm; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="G2TkRhkm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0507EC4AF17; Thu, 6 Jun 2024 09:42:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1717666968; bh=rYDwo9sVsMIRRs3ihHMD2TPD1n36mAZ6UOjA9MgTFl0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=G2TkRhkmkHjPelu0TX61Lw03mfsgAKX5AdeVNRWdi69bFB8h0qZsJnPFLrnCuPxku dxdFZfRwwZwOtg8OiNz43pfLyVhf2onir3ssxX3F1buE3GQT4llJfb1SaU9lXk1KvY CkG1TiSdf3YFb1CgChk2S7RyHCbrWYb4IOLWhybYbd55HfBQ+rCmSJEdR9k+MPybNL ZMna50fnozr8JAm3EzkevVB+iynVrPyA+BP+9FdkeaAJc8EwX+Q06hZluA80nBriBD vNw0aiZ8qa4baABrbRhOw2lK2CdvGaaK3q9nO5e9poi3W8Z9CBm8NxWQ2B1PMEhLBS Wp2yXdqXshmqQ== From: Lorenzo Pieralisi To: linux-kernel@vger.kernel.org Cc: Lorenzo Pieralisi , Robin Murphy , Marc Zyngier , Thomas Gleixner , Mark Rutland , "Rafael J. Wysocki" , linux-arm-kernel@lists.infradead.org, linux-acpi@vger.kernel.org, acpica-devel@lists.linux.dev Subject: [PATCH v6 1/1] irqchip/gic-v3: Enable non-coherent redistributors/ITSes ACPI probing Date: Thu, 6 Jun 2024 11:42:38 +0200 Message-Id: <20240606094238.757649-2-lpieralisi@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240606094238.757649-1-lpieralisi@kernel.org> References: <20240123110332.112797-1-lpieralisi@kernel.org> <20240606094238.757649-1-lpieralisi@kernel.org> Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The GIC architecture specification defines a set of registers for redistributors and ITSes that control the sharebility and cacheability attributes of redistributors/ITSes initiator ports on the interconnect (GICR_[V]PROPBASER, GICR_[V]PENDBASER, GITS_BASER). Architecturally the GIC provides a means to drive shareability and cacheability attributes signals but it is not mandatory for designs to wire up the corresponding interconnect signals that control the cacheability/shareability of transactions. Redistributors and ITSes interconnect ports can be connected to non-coherent interconnects that are not able to manage the shareability/cacheability attributes; this implicitly makes the redistributors and ITSes non-coherent observers. To enable non-coherent GIC designs on ACPI based systems, parse the MADT GICC/GICR/ITS subtables non-coherent flags to determine whether the respective components are non-coherent observers and force the shareability attributes to be programmed into the redistributors and ITSes registers. An ACPI global function (acpi_get_madt_revision()) is added to retrieve the MADT revision, in that it is essential to check the MADT revision before checking for flags that were added with MADT revision 7 so that if the kernel is booted with an ACPI MADT table with revision < 7 it skips parsing the newly added flags (that should be zeroed reserved values for MADT versions < 7 but they could turn out to be buggy and should be ignored). Signed-off-by: Lorenzo Pieralisi Reviewed-by: Robin Murphy Acked-by: Marc Zyngier Cc: Thomas Gleixner Cc: Robin Murphy Cc: Mark Rutland Cc: "Rafael J. Wysocki" Cc: Marc Zyngier --- drivers/acpi/processor_core.c | 15 +++++++++++++++ drivers/irqchip/irq-gic-v3-its.c | 4 ++++ drivers/irqchip/irq-gic-v3.c | 9 +++++++++ include/linux/acpi.h | 3 +++ 4 files changed, 31 insertions(+) diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c index b203cfe28550..915713c0e9b7 100644 --- a/drivers/acpi/processor_core.c +++ b/drivers/acpi/processor_core.c @@ -215,6 +215,21 @@ phys_cpuid_t __init acpi_map_madt_entry(u32 acpi_id) return rv; } +int __init acpi_get_madt_revision(void) +{ + struct acpi_table_header *madt = NULL; + int revision; + + if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0, &madt))) + return -EINVAL; + + revision = madt->revision; + + acpi_put_table(madt); + + return revision; +} + static phys_cpuid_t map_mat_entry(acpi_handle handle, int type, u32 acpi_id) { struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index 40ebf1726393..af5297ef2293 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -5600,6 +5600,10 @@ static int __init gic_acpi_parse_madt_its(union acpi_subtable_headers *header, goto node_err; } + if (acpi_get_madt_revision() >= 7 && + (its_entry->flags & ACPI_MADT_ITS_NON_COHERENT)) + its->flags |= ITS_FLAGS_FORCE_NON_SHAREABLE; + err = its_probe_one(its); if (!err) return 0; diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c index 6fb276504bcc..e4bc5f04226e 100644 --- a/drivers/irqchip/irq-gic-v3.c +++ b/drivers/irqchip/irq-gic-v3.c @@ -2349,6 +2349,11 @@ gic_acpi_parse_madt_redist(union acpi_subtable_headers *header, pr_err("Couldn't map GICR region @%llx\n", redist->base_address); return -ENOMEM; } + + if (acpi_get_madt_revision() >= 7 && + (redist->flags & ACPI_MADT_GICR_NON_COHERENT)) + gic_data.rdists.flags |= RDIST_FLAGS_FORCE_NON_SHAREABLE; + gic_request_region(redist->base_address, redist->length, "GICR"); gic_acpi_register_redist(redist->base_address, redist_base); @@ -2373,6 +2378,10 @@ gic_acpi_parse_madt_gicc(union acpi_subtable_headers *header, return -ENOMEM; gic_request_region(gicc->gicr_base_address, size, "GICR"); + if (acpi_get_madt_revision() >= 7 && + (gicc->flags & ACPI_MADT_GICC_NON_COHERENT)) + gic_data.rdists.flags |= RDIST_FLAGS_FORCE_NON_SHAREABLE; + gic_acpi_register_redist(gicc->gicr_base_address, redist_base); return 0; } diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 28c3fb2bef0d..000d339e1596 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -279,6 +279,9 @@ static inline bool invalid_phys_cpuid(phys_cpuid_t phys_id) return phys_id == PHYS_CPUID_INVALID; } + +int __init acpi_get_madt_revision(void); + /* Validate the processor object's proc_id */ bool acpi_duplicate_processor_id(int proc_id); /* Processor _CTS control */