hw/cxl/cxl-host.c - qemu - Git at Google

 /*
  * 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)
 {
     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, 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_reg;
     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_reg = cache_mem[R_CXL_HDM_DECODER0_TARGET_LIST_LO];
         target_reg >>= target_idx * 8;
     } else {
         target_reg = cache_mem[R_CXL_HDM_DECODER0_TARGET_LIST_LO];
         target_reg >>= (target_idx - 4) * 8;
     }
     *target = target_reg & 0xff;

     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);
             }
         }
     }
 }
	/*
	* 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)
	{
	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, 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_reg;
	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_reg = cache_mem[R_CXL_HDM_DECODER0_TARGET_LIST_LO];
	target_reg >>= target_idx * 8;
	} else {
	target_reg = cache_mem[R_CXL_HDM_DECODER0_TARGET_LIST_LO];
	target_reg >>= (target_idx - 4) * 8;
	}
	*target = target_reg & 0xff;

	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);
	}
	}
	}
	}