From patchwork Sat Dec 16 00:13:12 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jarred White X-Patchwork-Id: 755127 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 71E8C7E; Sat, 16 Dec 2023 00:13:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="Q7uIpsOv" Received: from localhost.localdomain (unknown [167.220.81.210]) by linux.microsoft.com (Postfix) with ESMTPSA id 7E9BC20446D3; Fri, 15 Dec 2023 16:13:37 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 7E9BC20446D3 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1702685617; bh=DStV9lsm6On3KW8OLJcekUkfoW3cgGVDLm76/JkJul0=; h=From:To:Subject:Date:From; b=Q7uIpsOvEYyIAi/REnu+ZoqvznbJgsj9NA2dmKTgwCdv79u1ntzIFx97x74ybix+8 L0uqEgwmLC186Z45Wtrn8nWbT4YMIrfXKzhr3tR8eckPteirjvVo5LOiHTYdG/YjXm BlyhOkRBx9rOiHlzHE6NPhwa58xlO3kCiGjO5p5Q= 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: [RESEND PATCH v2] acpi: Use access_width over register_width for system memory accesses Date: Fri, 15 Dec 2023 16:13:12 -0800 Message-Id: <20231216001312.1160-1-jarredwhite@linux.microsoft.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 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 bits we 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 --- Original thread https://lore.kernel.org/all/20230925180552.76071-1-jarredwhite@linux.microsoft.com/ --- changelog: v1-->v2: 1. Fixed coding style errors 2. Backwards compatibility with ioremapping of address still an open question. Suggestions are welcomed. drivers/acpi/cppc_acpi.c | 36 +++++++++++++++++++++++++++++++----- 1 file changed, 31 insertions(+), 5 deletions(-) diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index 7ff269a78c20..fb37e1727bf8 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c @@ -163,6 +163,13 @@ show_cppc_data(cppc_get_perf_caps, cppc_perf_caps, nominal_freq); show_cppc_data(cppc_get_perf_ctrs, cppc_perf_fb_ctrs, reference_perf); show_cppc_data(cppc_get_perf_ctrs, cppc_perf_fb_ctrs, wraparound_time); +/* Use access_width to determine the total number of bits */ +#define ACCESS_WIDTH_TO_BITS(reg) 8 << ((reg)->access_width - 1) + +/* Shift and apply the mask for CPC reads/writes */ +#define MASK_VAL(val) (((val) >> reg->bit_offset) & \ + GENMASK((reg->bit_width), 0)) + static ssize_t show_feedback_ctrs(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { @@ -777,6 +784,7 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr) } else if (gas_t->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) { if (gas_t->address) { void __iomem *addr; + size_t access_width; if (!osc_cpc_flexible_adr_space_confirmed) { pr_debug("Flexible address space capability not supported\n"); @@ -784,7 +792,8 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr) goto out_free; } - addr = ioremap(gas_t->address, gas_t->bit_width/8); + access_width = ACCESS_WIDTH_TO_BITS(gas_t) / 8; + addr = ioremap(gas_t->address, access_width); if (!addr) goto out_free; cpc_ptr->cpc_regs[i-2].sys_mem_vaddr = addr; @@ -980,6 +989,7 @@ int __weak cpc_write_ffh(int cpunum, struct cpc_reg *reg, u64 val) static int cpc_read(int cpu, struct cpc_register_resource *reg_res, u64 *val) { void __iomem *vaddr = NULL; + int size; int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpu); struct cpc_reg *reg = ®_res->cpc_entry.reg; @@ -991,7 +1001,7 @@ static int cpc_read(int cpu, struct cpc_register_resource *reg_res, u64 *val) *val = 0; if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) { - u32 width = 8 << (reg->access_width - 1); + u32 width = ACCESS_WIDTH_TO_BITS(reg); u32 val_u32; acpi_status status; @@ -1015,7 +1025,12 @@ static int cpc_read(int cpu, struct cpc_register_resource *reg_res, u64 *val) return acpi_os_read_memory((acpi_physical_address)reg->address, val, reg->bit_width); - switch (reg->bit_width) { + if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) + size = ACCESS_WIDTH_TO_BITS(reg); + else + size = reg->bit_width; + + switch (size) { case 8: *val = readb_relaxed(vaddr); break; @@ -1034,18 +1049,22 @@ static int cpc_read(int cpu, struct cpc_register_resource *reg_res, u64 *val) return -EFAULT; } + if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) + *val = MASK_VAL(*val); + return 0; } static int cpc_write(int cpu, struct cpc_register_resource *reg_res, u64 val) { int ret_val = 0; + int size; void __iomem *vaddr = NULL; int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpu); struct cpc_reg *reg = ®_res->cpc_entry.reg; if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) { - u32 width = 8 << (reg->access_width - 1); + u32 width = ACCESS_WIDTH_TO_BITS(reg); acpi_status status; status = acpi_os_write_port((acpi_io_address)reg->address, @@ -1067,7 +1086,14 @@ static int cpc_write(int cpu, struct cpc_register_resource *reg_res, u64 val) return acpi_os_write_memory((acpi_physical_address)reg->address, val, reg->bit_width); - switch (reg->bit_width) { + if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) { + size = ACCESS_WIDTH_TO_BITS(reg); + val = MASK_VAL(val); + } else { + size = reg->bit_width; + } + + switch (size) { case 8: writeb_relaxed(val, vaddr); break;