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authorDaniel Baumann <mail@daniel-baumann.ch>2025-06-06 10:05:23 +0000
committerDaniel Baumann <mail@daniel-baumann.ch>2025-06-06 10:05:23 +0000
commit755cc582a2473d06f3a2131d506d0311cc70e9f9 (patch)
tree3efb1ddb8d57bbb4539ac0d229b384871c57820f /hw/cxl/cxl-host.c
parentInitial commit. (diff)
downloadqemu-upstream.tar.xz
qemu-upstream.zip
Adding upstream version 1:7.2+dfsg.upstream/1%7.2+dfsgupstream
Signed-off-by: Daniel Baumann <mail@daniel-baumann.ch>
Diffstat (limited to 'hw/cxl/cxl-host.c')
-rw-r--r--hw/cxl/cxl-host.c340
1 files changed, 340 insertions, 0 deletions
diff --git a/hw/cxl/cxl-host.c b/hw/cxl/cxl-host.c
new file mode 100644
index 00000000..1adf6123
--- /dev/null
+++ b/hw/cxl/cxl-host.c
@@ -0,0 +1,340 @@
+/*
+ * CXL host parameter parsing routines
+ *
+ * Copyright (c) 2022 Huawei
+ * Modeled loosely on the NUMA options handling in hw/core/numa.c
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/units.h"
+#include "qemu/bitmap.h"
+#include "qemu/error-report.h"
+#include "qapi/error.h"
+#include "sysemu/qtest.h"
+#include "hw/boards.h"
+
+#include "qapi/qapi-visit-machine.h"
+#include "hw/cxl/cxl.h"
+#include "hw/cxl/cxl_host.h"
+#include "hw/pci/pci_bus.h"
+#include "hw/pci/pci_bridge.h"
+#include "hw/pci/pci_host.h"
+#include "hw/pci/pcie_port.h"
+#include "hw/pci-bridge/pci_expander_bridge.h"
+
+static void cxl_fixed_memory_window_config(CXLState *cxl_state,
+ CXLFixedMemoryWindowOptions *object,
+ Error **errp)
+{
+ g_autofree CXLFixedWindow *fw = g_malloc0(sizeof(*fw));
+ strList *target;
+ int i;
+
+ for (target = object->targets; target; target = target->next) {
+ fw->num_targets++;
+ }
+
+ fw->enc_int_ways = cxl_interleave_ways_enc(fw->num_targets, errp);
+ if (*errp) {
+ return;
+ }
+
+ fw->targets = g_malloc0_n(fw->num_targets, sizeof(*fw->targets));
+ for (i = 0, target = object->targets; target; i++, target = target->next) {
+ /* This link cannot be resolved yet, so stash the name for now */
+ fw->targets[i] = g_strdup(target->value);
+ }
+
+ if (object->size % (256 * MiB)) {
+ error_setg(errp,
+ "Size of a CXL fixed memory window must my a multiple of 256MiB");
+ return;
+ }
+ fw->size = object->size;
+
+ if (object->has_interleave_granularity) {
+ fw->enc_int_gran =
+ cxl_interleave_granularity_enc(object->interleave_granularity,
+ errp);
+ if (*errp) {
+ return;
+ }
+ } else {
+ /* Default to 256 byte interleave */
+ fw->enc_int_gran = 0;
+ }
+
+ cxl_state->fixed_windows = g_list_append(cxl_state->fixed_windows,
+ g_steal_pointer(&fw));
+
+ return;
+}
+
+void cxl_fmws_link_targets(CXLState *cxl_state, Error **errp)
+{
+ if (cxl_state && cxl_state->fixed_windows) {
+ GList *it;
+
+ for (it = cxl_state->fixed_windows; it; it = it->next) {
+ CXLFixedWindow *fw = it->data;
+ int i;
+
+ for (i = 0; i < fw->num_targets; i++) {
+ Object *o;
+ bool ambig;
+
+ o = object_resolve_path_type(fw->targets[i],
+ TYPE_PXB_CXL_DEVICE,
+ &ambig);
+ if (!o) {
+ error_setg(errp, "Could not resolve CXLFM target %s",
+ fw->targets[i]);
+ return;
+ }
+ fw->target_hbs[i] = PXB_CXL_DEV(o);
+ }
+ }
+ }
+}
+
+/* TODO: support, multiple hdm decoders */
+static bool cxl_hdm_find_target(uint32_t *cache_mem, hwaddr addr,
+ uint8_t *target)
+{
+ uint32_t ctrl;
+ uint32_t ig_enc;
+ uint32_t iw_enc;
+ uint32_t target_idx;
+
+ ctrl = cache_mem[R_CXL_HDM_DECODER0_CTRL];
+ if (!FIELD_EX32(ctrl, CXL_HDM_DECODER0_CTRL, COMMITTED)) {
+ return false;
+ }
+
+ ig_enc = FIELD_EX32(ctrl, CXL_HDM_DECODER0_CTRL, IG);
+ iw_enc = FIELD_EX32(ctrl, CXL_HDM_DECODER0_CTRL, IW);
+ target_idx = (addr / cxl_decode_ig(ig_enc)) % (1 << iw_enc);
+
+ if (target_idx < 4) {
+ *target = extract32(cache_mem[R_CXL_HDM_DECODER0_TARGET_LIST_LO],
+ target_idx * 8, 8);
+ } else {
+ *target = extract32(cache_mem[R_CXL_HDM_DECODER0_TARGET_LIST_HI],
+ (target_idx - 4) * 8, 8);
+ }
+
+ return true;
+}
+
+static PCIDevice *cxl_cfmws_find_device(CXLFixedWindow *fw, hwaddr addr)
+{
+ CXLComponentState *hb_cstate, *usp_cstate;
+ PCIHostState *hb;
+ CXLUpstreamPort *usp;
+ int rb_index;
+ uint32_t *cache_mem;
+ uint8_t target;
+ bool target_found;
+ PCIDevice *rp, *d;
+
+ /* Address is relative to memory region. Convert to HPA */
+ addr += fw->base;
+
+ rb_index = (addr / cxl_decode_ig(fw->enc_int_gran)) % fw->num_targets;
+ hb = PCI_HOST_BRIDGE(fw->target_hbs[rb_index]->cxl.cxl_host_bridge);
+ if (!hb || !hb->bus || !pci_bus_is_cxl(hb->bus)) {
+ return NULL;
+ }
+
+ hb_cstate = cxl_get_hb_cstate(hb);
+ if (!hb_cstate) {
+ return NULL;
+ }
+
+ cache_mem = hb_cstate->crb.cache_mem_registers;
+
+ target_found = cxl_hdm_find_target(cache_mem, addr, &target);
+ if (!target_found) {
+ return NULL;
+ }
+
+ rp = pcie_find_port_by_pn(hb->bus, target);
+ if (!rp) {
+ return NULL;
+ }
+
+ d = pci_bridge_get_sec_bus(PCI_BRIDGE(rp))->devices[0];
+ if (!d) {
+ return NULL;
+ }
+
+ if (object_dynamic_cast(OBJECT(d), TYPE_CXL_TYPE3)) {
+ return d;
+ }
+
+ /*
+ * Could also be a switch. Note only one level of switching currently
+ * supported.
+ */
+ if (!object_dynamic_cast(OBJECT(d), TYPE_CXL_USP)) {
+ return NULL;
+ }
+ usp = CXL_USP(d);
+
+ usp_cstate = cxl_usp_to_cstate(usp);
+ if (!usp_cstate) {
+ return NULL;
+ }
+
+ cache_mem = usp_cstate->crb.cache_mem_registers;
+
+ target_found = cxl_hdm_find_target(cache_mem, addr, &target);
+ if (!target_found) {
+ return NULL;
+ }
+
+ d = pcie_find_port_by_pn(&PCI_BRIDGE(d)->sec_bus, target);
+ if (!d) {
+ return NULL;
+ }
+
+ d = pci_bridge_get_sec_bus(PCI_BRIDGE(d))->devices[0];
+ if (!d) {
+ return NULL;
+ }
+
+ if (!object_dynamic_cast(OBJECT(d), TYPE_CXL_TYPE3)) {
+ return NULL;
+ }
+
+ return d;
+}
+
+static MemTxResult cxl_read_cfmws(void *opaque, hwaddr addr, uint64_t *data,
+ unsigned size, MemTxAttrs attrs)
+{
+ CXLFixedWindow *fw = opaque;
+ PCIDevice *d;
+
+ d = cxl_cfmws_find_device(fw, addr);
+ if (d == NULL) {
+ *data = 0;
+ /* Reads to invalid address return poison */
+ return MEMTX_ERROR;
+ }
+
+ return cxl_type3_read(d, addr + fw->base, data, size, attrs);
+}
+
+static MemTxResult cxl_write_cfmws(void *opaque, hwaddr addr,
+ uint64_t data, unsigned size,
+ MemTxAttrs attrs)
+{
+ CXLFixedWindow *fw = opaque;
+ PCIDevice *d;
+
+ d = cxl_cfmws_find_device(fw, addr);
+ if (d == NULL) {
+ /* Writes to invalid address are silent */
+ return MEMTX_OK;
+ }
+
+ return cxl_type3_write(d, addr + fw->base, data, size, attrs);
+}
+
+const MemoryRegionOps cfmws_ops = {
+ .read_with_attrs = cxl_read_cfmws,
+ .write_with_attrs = cxl_write_cfmws,
+ .endianness = DEVICE_LITTLE_ENDIAN,
+ .valid = {
+ .min_access_size = 1,
+ .max_access_size = 8,
+ .unaligned = true,
+ },
+ .impl = {
+ .min_access_size = 1,
+ .max_access_size = 8,
+ .unaligned = true,
+ },
+};
+
+static void machine_get_cxl(Object *obj, Visitor *v, const char *name,
+ void *opaque, Error **errp)
+{
+ CXLState *cxl_state = opaque;
+ bool value = cxl_state->is_enabled;
+
+ visit_type_bool(v, name, &value, errp);
+}
+
+static void machine_set_cxl(Object *obj, Visitor *v, const char *name,
+ void *opaque, Error **errp)
+{
+ CXLState *cxl_state = opaque;
+ bool value;
+
+ if (!visit_type_bool(v, name, &value, errp)) {
+ return;
+ }
+ cxl_state->is_enabled = value;
+}
+
+static void machine_get_cfmw(Object *obj, Visitor *v, const char *name,
+ void *opaque, Error **errp)
+{
+ CXLFixedMemoryWindowOptionsList **list = opaque;
+
+ visit_type_CXLFixedMemoryWindowOptionsList(v, name, list, errp);
+}
+
+static void machine_set_cfmw(Object *obj, Visitor *v, const char *name,
+ void *opaque, Error **errp)
+{
+ CXLState *state = opaque;
+ CXLFixedMemoryWindowOptionsList *cfmw_list = NULL;
+ CXLFixedMemoryWindowOptionsList *it;
+
+ visit_type_CXLFixedMemoryWindowOptionsList(v, name, &cfmw_list, errp);
+ if (!cfmw_list) {
+ return;
+ }
+
+ for (it = cfmw_list; it; it = it->next) {
+ cxl_fixed_memory_window_config(state, it->value, errp);
+ }
+ state->cfmw_list = cfmw_list;
+}
+
+void cxl_machine_init(Object *obj, CXLState *state)
+{
+ object_property_add(obj, "cxl", "bool", machine_get_cxl,
+ machine_set_cxl, NULL, state);
+ object_property_set_description(obj, "cxl",
+ "Set on/off to enable/disable "
+ "CXL instantiation");
+
+ object_property_add(obj, "cxl-fmw", "CXLFixedMemoryWindow",
+ machine_get_cfmw, machine_set_cfmw,
+ NULL, state);
+ object_property_set_description(obj, "cxl-fmw",
+ "CXL Fixed Memory Windows (array)");
+}
+
+void cxl_hook_up_pxb_registers(PCIBus *bus, CXLState *state, Error **errp)
+{
+ /* Walk the pci busses looking for pxb busses to hook up */
+ if (bus) {
+ QLIST_FOREACH(bus, &bus->child, sibling) {
+ if (!pci_bus_is_root(bus)) {
+ continue;
+ }
+ if (pci_bus_is_cxl(bus)) {
+ if (!state->is_enabled) {
+ error_setg(errp, "CXL host bridges present, but cxl=off");
+ return;
+ }
+ pxb_cxl_hook_up_registers(state, bus, errp);
+ }
+ }
+ }
+}