Source-Changes-HG archive
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]
[src/trunk]: src/sys/dev/acpi acpi: Add support for ACPI Platform Communicati...
details: https://anonhg.NetBSD.org/src/rev/a2337d454a11
branches: trunk
changeset: 947218:a2337d454a11
user: jmcneill <jmcneill%NetBSD.org@localhost>
date: Sun Dec 13 20:27:53 2020 +0000
description:
acpi: Add support for ACPI Platform Communications Channel (PCC).
diffstat:
sys/dev/acpi/acpi_pcc.c | 389 ++++++++++++++++++++++++++++++++++++++++++++++++
sys/dev/acpi/acpi_pcc.h | 38 ++++
sys/dev/acpi/files.acpi | 7 +-
3 files changed, 433 insertions(+), 1 deletions(-)
diffs (truncated from 456 to 300 lines):
diff -r dfdfd4be4cb0 -r a2337d454a11 sys/dev/acpi/acpi_pcc.c
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/sys/dev/acpi/acpi_pcc.c Sun Dec 13 20:27:53 2020 +0000
@@ -0,0 +1,389 @@
+/* $NetBSD: acpi_pcc.c,v 1.1 2020/12/13 20:27:53 jmcneill Exp $ */
+
+/*-
+ * Copyright (c) 2020 Jared McNeill <jmcneill%invisible.ca@localhost>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/*
+ * Platform Communications Channel (PCC) device driver.
+ */
+
+#include <sys/cdefs.h>
+__KERNEL_RCSID(0, "$NetBSD: acpi_pcc.c,v 1.1 2020/12/13 20:27:53 jmcneill Exp $");
+
+#include <sys/param.h>
+#include <sys/bus.h>
+#include <sys/cpu.h>
+#include <sys/device.h>
+#include <sys/kmem.h>
+
+#include <dev/acpi/acpireg.h>
+#include <dev/acpi/acpivar.h>
+#include <dev/acpi/acpi_pcc.h>
+
+#define PCC_MEMORY_BARRIER() membar_sync()
+#if defined(__aarch64__)
+#define PCC_DMA_BARRIER() __asm __volatile("dsb sy" ::: "memory")
+#else
+#error PCC_BARRIER not implemented on this platform
+#endif
+
+#define PCC_SIGNATURE(space_id) (0x50434300 | (space_id))
+#define PCC_STATUS_COMMAND_COMPLETE __BIT(0)
+#define PCC_STATUS_COMMAND_ERROR __BIT(2)
+
+struct pcc_register {
+ ACPI_GENERIC_ADDRESS reg_addr;
+ uint64_t reg_preserve;
+ uint64_t reg_set;
+};
+
+struct pcc_subspace {
+ uint8_t ss_id;
+ uint8_t ss_type;
+ void * ss_data;
+ size_t ss_len;
+ struct pcc_register ss_doorbell_reg;
+ uint32_t ss_latency;
+ uint32_t ss_turnaround;
+ kmutex_t ss_lock;
+};
+
+struct pcc_softc {
+ device_t sc_dev;
+ struct pcc_subspace * sc_ss;
+ u_int sc_nss;
+};
+
+typedef void (*pcc_subspace_callback)(ACPI_SUBTABLE_HEADER *, uint8_t, void *);
+
+static int pcc_match(device_t, cfdata_t, void *);
+static void pcc_attach(device_t, device_t, void *);
+
+static uint8_t pcc_subspace_foreach(ACPI_TABLE_PCCT *,
+ pcc_subspace_callback, void *);
+static void pcc_subspace_attach(ACPI_SUBTABLE_HEADER *, uint8_t, void *);
+
+static struct pcc_softc *pcc_softc = NULL;
+
+CFATTACH_DECL_NEW(acpipcc, sizeof(struct pcc_softc),
+ pcc_match, pcc_attach, NULL, NULL);
+
+static int
+pcc_match(device_t parent, cfdata_t cf, void *aux)
+{
+ ACPI_TABLE_HEADER *hdrp = aux;
+
+ return memcmp(hdrp->Signature, ACPI_SIG_PCCT, ACPI_NAMESEG_SIZE) == 0;
+}
+
+static void
+pcc_attach(device_t parent, device_t self, void *aux)
+{
+ struct pcc_softc * const sc = device_private(self);
+ ACPI_TABLE_PCCT *pcct = aux;
+ u_int count;
+
+ if (pcc_softc != NULL) {
+ aprint_error(": Already attached!\n");
+ return;
+ }
+
+ count = pcc_subspace_foreach(pcct, NULL, NULL);
+ if (count == 0) {
+ aprint_error(": No subspaces found!\n");
+ return;
+ }
+
+ aprint_naive("\n");
+ aprint_normal(": Platform Communications Channel, %u subspace%s\n",
+ count, count == 1 ? "" : "s");
+
+ sc->sc_dev = self;
+ sc->sc_nss = count;
+ sc->sc_ss = kmem_zalloc(count * sizeof(*sc->sc_ss), KM_SLEEP);
+ pcc_subspace_foreach(pcct, pcc_subspace_attach, sc);
+
+ pcc_softc = sc;
+}
+
+/*
+ * pcc_subspace_foreach --
+ *
+ * Find all subspaces defined in the PCCT table. If a 'func' callback
+ * is provided, the callback is invoked for each subspace with the
+ * table pointer, subspace ID, and 'arg' as arguments. Returns the
+ * number of subspaces found.
+ */
+static uint8_t
+pcc_subspace_foreach(ACPI_TABLE_PCCT *pcct, pcc_subspace_callback func,
+ void *arg)
+{
+ ACPI_SUBTABLE_HEADER *header;
+ char *ptr, *end;
+ uint8_t count;
+
+ end = (char *)pcct + pcct->Header.Length;
+ ptr = (char *)pcct + sizeof(*pcct);
+ count = 0;
+
+ while (ptr < end && count < 255) {
+ header = (ACPI_SUBTABLE_HEADER *)ptr;
+ if (header->Length == 0 || ptr + header->Length > end) {
+ break;
+ }
+ if (func != NULL) {
+ func(header, count, arg);
+ }
+ ++count;
+ ptr += header->Length;
+ }
+
+ return count;
+}
+
+/*
+ * pcc_subspace_attach --
+ *
+ * Allocate resources for a PCC subspace.
+ */
+static void
+pcc_subspace_attach(ACPI_SUBTABLE_HEADER *header, uint8_t id, void *arg)
+{
+ struct pcc_softc * const sc = arg;
+ struct pcc_subspace * const ss = &sc->sc_ss[id];
+ ACPI_PCCT_SUBSPACE *generic = (ACPI_PCCT_SUBSPACE *)header;
+
+ ss->ss_id = id;
+ ss->ss_type = header->Type;
+ ss->ss_data = AcpiOsMapMemory(generic->BaseAddress, generic->Length);
+ if (ss->ss_data == NULL) {
+ panic("%s: couldn't map subspace 0x%02x at 0x%016" PRIx64,
+ device_xname(sc->sc_dev), id, generic->BaseAddress);
+ }
+ ss->ss_len = generic->Length;
+ ss->ss_doorbell_reg.reg_addr = generic->DoorbellRegister;
+ ss->ss_doorbell_reg.reg_preserve = generic->PreserveMask;
+ ss->ss_doorbell_reg.reg_set = generic->WriteMask;
+ mutex_init(&ss->ss_lock, MUTEX_DEFAULT, IPL_NONE);
+}
+
+/*
+ * pcc_wait_command --
+ *
+ * Wait for command complete to be set on a PCC subspace, with timeout.
+ */
+static ACPI_STATUS
+pcc_wait_command(struct pcc_subspace *ss, bool first)
+{
+ volatile ACPI_PCCT_SHARED_MEMORY *shmem;
+ int retry;
+
+ switch (ss->ss_type) {
+ case ACPI_PCCT_TYPE_GENERIC_SUBSPACE:
+ /*
+ * OSPM does not have to wait for command complete before
+ * sending the first command.
+ */
+ if (first) {
+ return AE_OK;
+ }
+ /* FALLTHROUGH */
+
+ case ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE:
+ case ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE_TYPE2:
+ /*
+ * Wait for the command complete bit to be set in the status
+ * register.
+ */
+ shmem = ss->ss_data;
+ retry = imax(1000, ss->ss_turnaround + ss->ss_latency * 100);
+ while (retry > 0) {
+ PCC_MEMORY_BARRIER();
+ if ((shmem->Status & PCC_STATUS_COMMAND_COMPLETE) != 0)
+ return AE_OK;
+ delay(10);
+ retry -= 10;
+ }
+ return AE_TIME;
+
+ default:
+ return AE_NOT_IMPLEMENTED;
+ }
+}
+
+/*
+ * pcc_doorbell --
+ *
+ * Ring the door bell by writing to the doorbell register.
+ */
+static ACPI_STATUS
+pcc_doorbell(struct pcc_register *reg)
+{
+ ACPI_STATUS rv;
+ UINT64 val;
+
+ rv = AcpiRead(&val, ®->reg_addr);
+ if (ACPI_FAILURE(rv)) {
+ return rv;
+ }
+ val &= reg->reg_preserve;
+ val |= reg->reg_set;
+ return AcpiWrite(val, ®->reg_addr);
+}
+
+/*
+ * pcc_send_command --
+ *
+ * Write a command into PCC subspace and ring the doorbell.
+ */
+static ACPI_STATUS
+pcc_send_command(struct pcc_subspace *ss, ACPI_GENERIC_ADDRESS *reg,
+ uint32_t command, int flags, ACPI_INTEGER val)
+{
+ volatile ACPI_PCCT_SHARED_MEMORY *shmem = ss->ss_data;
+ uint8_t *data = __UNVOLATILE(shmem + 1);
+ UINT64 tmp, mask;
+
+ KASSERT(ss->ss_type == ACPI_PCCT_TYPE_GENERIC_SUBSPACE ||
+ ss->ss_type == ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE ||
+ ss->ss_type == ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE_TYPE2);
+
+ shmem->Signature = PCC_SIGNATURE(ss->ss_id);
+ shmem->Command = command & 0xff;
+ if ((flags & PCC_WRITE) != 0) {
+ mask = __BITS(reg->BitOffset + reg->BitWidth - 1,
+ reg->BitOffset);
+ ACPI_MOVE_64_TO_64(&tmp, data + reg->Address);
+ tmp &= mask;
+ tmp |= __SHIFTIN(val, mask);
+ ACPI_MOVE_64_TO_64(data + reg->Address, &tmp);
+ }
+ PCC_MEMORY_BARRIER();
+ shmem->Status &= ~(PCC_STATUS_COMMAND_COMPLETE |
+ PCC_STATUS_COMMAND_ERROR);
+ PCC_DMA_BARRIER();
+
+ return pcc_doorbell(&ss->ss_doorbell_reg);
+}
+
+/*
+ * pcc_receive_response --
+ *
+ * Process a command response in PCC subspace.
+ */
Home |
Main Index |
Thread Index |
Old Index