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|
// SPDX-License-Identifier: GPL-2.0-only
/* Copyright(c) 2022 Intel Corporation. All rights reserved. */
#include <linux/seq_file.h>
#include <linux/device.h>
#include <linux/delay.h>
#include "cxlmem.h"
#include "core.h"
/**
* DOC: cxl core hdm
*
* Compute Express Link Host Managed Device Memory, starting with the
* CXL 2.0 specification, is managed by an array of HDM Decoder register
* instances per CXL port and per CXL endpoint. Define common helpers
* for enumerating these registers and capabilities.
*/
DECLARE_RWSEM(cxl_dpa_rwsem);
static int add_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld,
int *target_map)
{
int rc;
rc = cxl_decoder_add_locked(cxld, target_map);
if (rc) {
put_device(&cxld->dev);
dev_err(&port->dev, "Failed to add decoder\n");
return rc;
}
rc = cxl_decoder_autoremove(&port->dev, cxld);
if (rc)
return rc;
dev_dbg(&cxld->dev, "Added to port %s\n", dev_name(&port->dev));
return 0;
}
/*
* Per the CXL specification (8.2.5.12 CXL HDM Decoder Capability Structure)
* single ported host-bridges need not publish a decoder capability when a
* passthrough decode can be assumed, i.e. all transactions that the uport sees
* are claimed and passed to the single dport. Disable the range until the first
* CXL region is enumerated / activated.
*/
int devm_cxl_add_passthrough_decoder(struct cxl_port *port)
{
struct cxl_switch_decoder *cxlsd;
struct cxl_dport *dport = NULL;
int single_port_map[1];
unsigned long index;
cxlsd = cxl_switch_decoder_alloc(port, 1);
if (IS_ERR(cxlsd))
return PTR_ERR(cxlsd);
device_lock_assert(&port->dev);
xa_for_each(&port->dports, index, dport)
break;
single_port_map[0] = dport->port_id;
return add_hdm_decoder(port, &cxlsd->cxld, single_port_map);
}
EXPORT_SYMBOL_NS_GPL(devm_cxl_add_passthrough_decoder, CXL);
static void parse_hdm_decoder_caps(struct cxl_hdm *cxlhdm)
{
u32 hdm_cap;
hdm_cap = readl(cxlhdm->regs.hdm_decoder + CXL_HDM_DECODER_CAP_OFFSET);
cxlhdm->decoder_count = cxl_hdm_decoder_count(hdm_cap);
cxlhdm->target_count =
FIELD_GET(CXL_HDM_DECODER_TARGET_COUNT_MASK, hdm_cap);
if (FIELD_GET(CXL_HDM_DECODER_INTERLEAVE_11_8, hdm_cap))
cxlhdm->interleave_mask |= GENMASK(11, 8);
if (FIELD_GET(CXL_HDM_DECODER_INTERLEAVE_14_12, hdm_cap))
cxlhdm->interleave_mask |= GENMASK(14, 12);
}
static int map_hdm_decoder_regs(struct cxl_port *port, void __iomem *crb,
struct cxl_component_regs *regs)
{
struct cxl_register_map map = {
.host = &port->dev,
.resource = port->component_reg_phys,
.base = crb,
.max_size = CXL_COMPONENT_REG_BLOCK_SIZE,
};
cxl_probe_component_regs(&port->dev, crb, &map.component_map);
if (!map.component_map.hdm_decoder.valid) {
dev_dbg(&port->dev, "HDM decoder registers not implemented\n");
/* unique error code to indicate no HDM decoder capability */
return -ENODEV;
}
return cxl_map_component_regs(&map, regs, BIT(CXL_CM_CAP_CAP_ID_HDM));
}
static bool should_emulate_decoders(struct cxl_endpoint_dvsec_info *info)
{
struct cxl_hdm *cxlhdm;
void __iomem *hdm;
u32 ctrl;
int i;
if (!info)
return false;
cxlhdm = dev_get_drvdata(&info->port->dev);
hdm = cxlhdm->regs.hdm_decoder;
if (!hdm)
return true;
/*
* If HDM decoders are present and the driver is in control of
* Mem_Enable skip DVSEC based emulation
*/
if (!info->mem_enabled)
return false;
/*
* If any decoders are committed already, there should not be any
* emulated DVSEC decoders.
*/
for (i = 0; i < cxlhdm->decoder_count; i++) {
ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(i));
dev_dbg(&info->port->dev,
"decoder%d.%d: committed: %ld base: %#x_%.8x size: %#x_%.8x\n",
info->port->id, i,
FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMITTED, ctrl),
readl(hdm + CXL_HDM_DECODER0_BASE_HIGH_OFFSET(i)),
readl(hdm + CXL_HDM_DECODER0_BASE_LOW_OFFSET(i)),
readl(hdm + CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(i)),
readl(hdm + CXL_HDM_DECODER0_SIZE_LOW_OFFSET(i)));
if (FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMITTED, ctrl))
return false;
}
return true;
}
/**
* devm_cxl_setup_hdm - map HDM decoder component registers
* @port: cxl_port to map
* @info: cached DVSEC range register info
*/
struct cxl_hdm *devm_cxl_setup_hdm(struct cxl_port *port,
struct cxl_endpoint_dvsec_info *info)
{
struct device *dev = &port->dev;
struct cxl_hdm *cxlhdm;
void __iomem *crb;
int rc;
cxlhdm = devm_kzalloc(dev, sizeof(*cxlhdm), GFP_KERNEL);
if (!cxlhdm)
return ERR_PTR(-ENOMEM);
cxlhdm->port = port;
dev_set_drvdata(dev, cxlhdm);
crb = ioremap(port->component_reg_phys, CXL_COMPONENT_REG_BLOCK_SIZE);
if (!crb && info && info->mem_enabled) {
cxlhdm->decoder_count = info->ranges;
return cxlhdm;
} else if (!crb) {
dev_err(dev, "No component registers mapped\n");
return ERR_PTR(-ENXIO);
}
rc = map_hdm_decoder_regs(port, crb, &cxlhdm->regs);
iounmap(crb);
if (rc)
return ERR_PTR(rc);
parse_hdm_decoder_caps(cxlhdm);
if (cxlhdm->decoder_count == 0) {
dev_err(dev, "Spec violation. Caps invalid\n");
return ERR_PTR(-ENXIO);
}
/*
* Now that the hdm capability is parsed, decide if range
* register emulation is needed and fixup cxlhdm accordingly.
*/
if (should_emulate_decoders(info)) {
dev_dbg(dev, "Fallback map %d range register%s\n", info->ranges,
info->ranges > 1 ? "s" : "");
cxlhdm->decoder_count = info->ranges;
}
return cxlhdm;
}
EXPORT_SYMBOL_NS_GPL(devm_cxl_setup_hdm, CXL);
static void __cxl_dpa_debug(struct seq_file *file, struct resource *r, int depth)
{
unsigned long long start = r->start, end = r->end;
seq_printf(file, "%*s%08llx-%08llx : %s\n", depth * 2, "", start, end,
r->name);
}
void cxl_dpa_debug(struct seq_file *file, struct cxl_dev_state *cxlds)
{
struct resource *p1, *p2;
down_read(&cxl_dpa_rwsem);
for (p1 = cxlds->dpa_res.child; p1; p1 = p1->sibling) {
__cxl_dpa_debug(file, p1, 0);
for (p2 = p1->child; p2; p2 = p2->sibling)
__cxl_dpa_debug(file, p2, 1);
}
up_read(&cxl_dpa_rwsem);
}
EXPORT_SYMBOL_NS_GPL(cxl_dpa_debug, CXL);
/*
* Must be called in a context that synchronizes against this decoder's
* port ->remove() callback (like an endpoint decoder sysfs attribute)
*/
static void __cxl_dpa_release(struct cxl_endpoint_decoder *cxled)
{
struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
struct cxl_port *port = cxled_to_port(cxled);
struct cxl_dev_state *cxlds = cxlmd->cxlds;
struct resource *res = cxled->dpa_res;
resource_size_t skip_start;
lockdep_assert_held_write(&cxl_dpa_rwsem);
/* save @skip_start, before @res is released */
skip_start = res->start - cxled->skip;
__release_region(&cxlds->dpa_res, res->start, resource_size(res));
if (cxled->skip)
__release_region(&cxlds->dpa_res, skip_start, cxled->skip);
cxled->skip = 0;
cxled->dpa_res = NULL;
put_device(&cxled->cxld.dev);
port->hdm_end--;
}
static void cxl_dpa_release(void *cxled)
{
down_write(&cxl_dpa_rwsem);
__cxl_dpa_release(cxled);
up_write(&cxl_dpa_rwsem);
}
/*
* Must be called from context that will not race port device
* unregistration, like decoder sysfs attribute methods
*/
static void devm_cxl_dpa_release(struct cxl_endpoint_decoder *cxled)
{
struct cxl_port *port = cxled_to_port(cxled);
lockdep_assert_held_write(&cxl_dpa_rwsem);
devm_remove_action(&port->dev, cxl_dpa_release, cxled);
__cxl_dpa_release(cxled);
}
static int __cxl_dpa_reserve(struct cxl_endpoint_decoder *cxled,
resource_size_t base, resource_size_t len,
resource_size_t skipped)
{
struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
struct cxl_port *port = cxled_to_port(cxled);
struct cxl_dev_state *cxlds = cxlmd->cxlds;
struct device *dev = &port->dev;
struct resource *res;
lockdep_assert_held_write(&cxl_dpa_rwsem);
if (!len) {
dev_warn(dev, "decoder%d.%d: empty reservation attempted\n",
port->id, cxled->cxld.id);
return -EINVAL;
}
if (cxled->dpa_res) {
dev_dbg(dev, "decoder%d.%d: existing allocation %pr assigned\n",
port->id, cxled->cxld.id, cxled->dpa_res);
return -EBUSY;
}
if (port->hdm_end + 1 != cxled->cxld.id) {
/*
* Assumes alloc and commit order is always in hardware instance
* order per expectations from 8.2.5.12.20 Committing Decoder
* Programming that enforce decoder[m] committed before
* decoder[m+1] commit start.
*/
dev_dbg(dev, "decoder%d.%d: expected decoder%d.%d\n", port->id,
cxled->cxld.id, port->id, port->hdm_end + 1);
return -EBUSY;
}
if (skipped) {
res = __request_region(&cxlds->dpa_res, base - skipped, skipped,
dev_name(&cxled->cxld.dev), 0);
if (!res) {
dev_dbg(dev,
"decoder%d.%d: failed to reserve skipped space\n",
port->id, cxled->cxld.id);
return -EBUSY;
}
}
res = __request_region(&cxlds->dpa_res, base, len,
dev_name(&cxled->cxld.dev), 0);
if (!res) {
dev_dbg(dev, "decoder%d.%d: failed to reserve allocation\n",
port->id, cxled->cxld.id);
if (skipped)
__release_region(&cxlds->dpa_res, base - skipped,
skipped);
return -EBUSY;
}
cxled->dpa_res = res;
cxled->skip = skipped;
if (resource_contains(&cxlds->pmem_res, res))
cxled->mode = CXL_DECODER_PMEM;
else if (resource_contains(&cxlds->ram_res, res))
cxled->mode = CXL_DECODER_RAM;
else {
dev_dbg(dev, "decoder%d.%d: %pr mixed\n", port->id,
cxled->cxld.id, cxled->dpa_res);
cxled->mode = CXL_DECODER_MIXED;
}
port->hdm_end++;
get_device(&cxled->cxld.dev);
return 0;
}
int devm_cxl_dpa_reserve(struct cxl_endpoint_decoder *cxled,
resource_size_t base, resource_size_t len,
resource_size_t skipped)
{
struct cxl_port *port = cxled_to_port(cxled);
int rc;
down_write(&cxl_dpa_rwsem);
rc = __cxl_dpa_reserve(cxled, base, len, skipped);
up_write(&cxl_dpa_rwsem);
if (rc)
return rc;
return devm_add_action_or_reset(&port->dev, cxl_dpa_release, cxled);
}
EXPORT_SYMBOL_NS_GPL(devm_cxl_dpa_reserve, CXL);
resource_size_t cxl_dpa_size(struct cxl_endpoint_decoder *cxled)
{
resource_size_t size = 0;
down_read(&cxl_dpa_rwsem);
if (cxled->dpa_res)
size = resource_size(cxled->dpa_res);
up_read(&cxl_dpa_rwsem);
return size;
}
resource_size_t cxl_dpa_resource_start(struct cxl_endpoint_decoder *cxled)
{
resource_size_t base = -1;
down_read(&cxl_dpa_rwsem);
if (cxled->dpa_res)
base = cxled->dpa_res->start;
up_read(&cxl_dpa_rwsem);
return base;
}
int cxl_dpa_free(struct cxl_endpoint_decoder *cxled)
{
struct cxl_port *port = cxled_to_port(cxled);
struct device *dev = &cxled->cxld.dev;
int rc;
down_write(&cxl_dpa_rwsem);
if (!cxled->dpa_res) {
rc = 0;
goto out;
}
if (cxled->cxld.region) {
dev_dbg(dev, "decoder assigned to: %s\n",
dev_name(&cxled->cxld.region->dev));
rc = -EBUSY;
goto out;
}
if (cxled->cxld.flags & CXL_DECODER_F_ENABLE) {
dev_dbg(dev, "decoder enabled\n");
rc = -EBUSY;
goto out;
}
if (cxled->cxld.id != port->hdm_end) {
dev_dbg(dev, "expected decoder%d.%d\n", port->id,
port->hdm_end);
rc = -EBUSY;
goto out;
}
devm_cxl_dpa_release(cxled);
rc = 0;
out:
up_write(&cxl_dpa_rwsem);
return rc;
}
int cxl_dpa_set_mode(struct cxl_endpoint_decoder *cxled,
enum cxl_decoder_mode mode)
{
struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
struct cxl_dev_state *cxlds = cxlmd->cxlds;
struct device *dev = &cxled->cxld.dev;
int rc;
switch (mode) {
case CXL_DECODER_RAM:
case CXL_DECODER_PMEM:
break;
default:
dev_dbg(dev, "unsupported mode: %d\n", mode);
return -EINVAL;
}
down_write(&cxl_dpa_rwsem);
if (cxled->cxld.flags & CXL_DECODER_F_ENABLE) {
rc = -EBUSY;
goto out;
}
/*
* Only allow modes that are supported by the current partition
* configuration
*/
if (mode == CXL_DECODER_PMEM && !resource_size(&cxlds->pmem_res)) {
dev_dbg(dev, "no available pmem capacity\n");
rc = -ENXIO;
goto out;
}
if (mode == CXL_DECODER_RAM && !resource_size(&cxlds->ram_res)) {
dev_dbg(dev, "no available ram capacity\n");
rc = -ENXIO;
goto out;
}
cxled->mode = mode;
rc = 0;
out:
up_write(&cxl_dpa_rwsem);
return rc;
}
int cxl_dpa_alloc(struct cxl_endpoint_decoder *cxled, unsigned long long size)
{
struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
resource_size_t free_ram_start, free_pmem_start;
struct cxl_port *port = cxled_to_port(cxled);
struct cxl_dev_state *cxlds = cxlmd->cxlds;
struct device *dev = &cxled->cxld.dev;
resource_size_t start, avail, skip;
struct resource *p, *last;
int rc;
down_write(&cxl_dpa_rwsem);
if (cxled->cxld.region) {
dev_dbg(dev, "decoder attached to %s\n",
dev_name(&cxled->cxld.region->dev));
rc = -EBUSY;
goto out;
}
if (cxled->cxld.flags & CXL_DECODER_F_ENABLE) {
dev_dbg(dev, "decoder enabled\n");
rc = -EBUSY;
goto out;
}
for (p = cxlds->ram_res.child, last = NULL; p; p = p->sibling)
last = p;
if (last)
free_ram_start = last->end + 1;
else
free_ram_start = cxlds->ram_res.start;
for (p = cxlds->pmem_res.child, last = NULL; p; p = p->sibling)
last = p;
if (last)
free_pmem_start = last->end + 1;
else
free_pmem_start = cxlds->pmem_res.start;
if (cxled->mode == CXL_DECODER_RAM) {
start = free_ram_start;
avail = cxlds->ram_res.end - start + 1;
skip = 0;
} else if (cxled->mode == CXL_DECODER_PMEM) {
resource_size_t skip_start, skip_end;
start = free_pmem_start;
avail = cxlds->pmem_res.end - start + 1;
skip_start = free_ram_start;
/*
* If some pmem is already allocated, then that allocation
* already handled the skip.
*/
if (cxlds->pmem_res.child &&
skip_start == cxlds->pmem_res.child->start)
skip_end = skip_start - 1;
else
skip_end = start - 1;
skip = skip_end - skip_start + 1;
} else {
dev_dbg(dev, "mode not set\n");
rc = -EINVAL;
goto out;
}
if (size > avail) {
dev_dbg(dev, "%pa exceeds available %s capacity: %pa\n", &size,
cxled->mode == CXL_DECODER_RAM ? "ram" : "pmem",
&avail);
rc = -ENOSPC;
goto out;
}
rc = __cxl_dpa_reserve(cxled, start, size, skip);
out:
up_write(&cxl_dpa_rwsem);
if (rc)
return rc;
return devm_add_action_or_reset(&port->dev, cxl_dpa_release, cxled);
}
static void cxld_set_interleave(struct cxl_decoder *cxld, u32 *ctrl)
{
u16 eig;
u8 eiw;
/*
* Input validation ensures these warns never fire, but otherwise
* suppress unititalized variable usage warnings.
*/
if (WARN_ONCE(ways_to_eiw(cxld->interleave_ways, &eiw),
"invalid interleave_ways: %d\n", cxld->interleave_ways))
return;
if (WARN_ONCE(granularity_to_eig(cxld->interleave_granularity, &eig),
"invalid interleave_granularity: %d\n",
cxld->interleave_granularity))
return;
u32p_replace_bits(ctrl, eig, CXL_HDM_DECODER0_CTRL_IG_MASK);
u32p_replace_bits(ctrl, eiw, CXL_HDM_DECODER0_CTRL_IW_MASK);
*ctrl |= CXL_HDM_DECODER0_CTRL_COMMIT;
}
static void cxld_set_type(struct cxl_decoder *cxld, u32 *ctrl)
{
u32p_replace_bits(ctrl,
!!(cxld->target_type == CXL_DECODER_HOSTONLYMEM),
CXL_HDM_DECODER0_CTRL_HOSTONLY);
}
static int cxlsd_set_targets(struct cxl_switch_decoder *cxlsd, u64 *tgt)
{
struct cxl_dport **t = &cxlsd->target[0];
int ways = cxlsd->cxld.interleave_ways;
if (dev_WARN_ONCE(&cxlsd->cxld.dev,
ways > 8 || ways > cxlsd->nr_targets,
"ways: %d overflows targets: %d\n", ways,
cxlsd->nr_targets))
return -ENXIO;
*tgt = FIELD_PREP(GENMASK(7, 0), t[0]->port_id);
if (ways > 1)
*tgt |= FIELD_PREP(GENMASK(15, 8), t[1]->port_id);
if (ways > 2)
*tgt |= FIELD_PREP(GENMASK(23, 16), t[2]->port_id);
if (ways > 3)
*tgt |= FIELD_PREP(GENMASK(31, 24), t[3]->port_id);
if (ways > 4)
*tgt |= FIELD_PREP(GENMASK_ULL(39, 32), t[4]->port_id);
if (ways > 5)
*tgt |= FIELD_PREP(GENMASK_ULL(47, 40), t[5]->port_id);
if (ways > 6)
*tgt |= FIELD_PREP(GENMASK_ULL(55, 48), t[6]->port_id);
if (ways > 7)
*tgt |= FIELD_PREP(GENMASK_ULL(63, 56), t[7]->port_id);
return 0;
}
/*
* Per CXL 2.0 8.2.5.12.20 Committing Decoder Programming, hardware must set
* committed or error within 10ms, but just be generous with 20ms to account for
* clock skew and other marginal behavior
*/
#define COMMIT_TIMEOUT_MS 20
static int cxld_await_commit(void __iomem *hdm, int id)
{
u32 ctrl;
int i;
for (i = 0; i < COMMIT_TIMEOUT_MS; i++) {
ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(id));
if (FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMIT_ERROR, ctrl)) {
ctrl &= ~CXL_HDM_DECODER0_CTRL_COMMIT;
writel(ctrl, hdm + CXL_HDM_DECODER0_CTRL_OFFSET(id));
return -EIO;
}
if (FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMITTED, ctrl))
return 0;
fsleep(1000);
}
return -ETIMEDOUT;
}
static int cxl_decoder_commit(struct cxl_decoder *cxld)
{
struct cxl_port *port = to_cxl_port(cxld->dev.parent);
struct cxl_hdm *cxlhdm = dev_get_drvdata(&port->dev);
void __iomem *hdm = cxlhdm->regs.hdm_decoder;
int id = cxld->id, rc;
u64 base, size;
u32 ctrl;
if (cxld->flags & CXL_DECODER_F_ENABLE)
return 0;
if (port->commit_end + 1 != id) {
dev_dbg(&port->dev,
"%s: out of order commit, expected decoder%d.%d\n",
dev_name(&cxld->dev), port->id, port->commit_end + 1);
return -EBUSY;
}
down_read(&cxl_dpa_rwsem);
/* common decoder settings */
ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(cxld->id));
cxld_set_interleave(cxld, &ctrl);
cxld_set_type(cxld, &ctrl);
base = cxld->hpa_range.start;
size = range_len(&cxld->hpa_range);
writel(upper_32_bits(base), hdm + CXL_HDM_DECODER0_BASE_HIGH_OFFSET(id));
writel(lower_32_bits(base), hdm + CXL_HDM_DECODER0_BASE_LOW_OFFSET(id));
writel(upper_32_bits(size), hdm + CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(id));
writel(lower_32_bits(size), hdm + CXL_HDM_DECODER0_SIZE_LOW_OFFSET(id));
if (is_switch_decoder(&cxld->dev)) {
struct cxl_switch_decoder *cxlsd =
to_cxl_switch_decoder(&cxld->dev);
void __iomem *tl_hi = hdm + CXL_HDM_DECODER0_TL_HIGH(id);
void __iomem *tl_lo = hdm + CXL_HDM_DECODER0_TL_LOW(id);
u64 targets;
rc = cxlsd_set_targets(cxlsd, &targets);
if (rc) {
dev_dbg(&port->dev, "%s: target configuration error\n",
dev_name(&cxld->dev));
goto err;
}
writel(upper_32_bits(targets), tl_hi);
writel(lower_32_bits(targets), tl_lo);
} else {
struct cxl_endpoint_decoder *cxled =
to_cxl_endpoint_decoder(&cxld->dev);
void __iomem *sk_hi = hdm + CXL_HDM_DECODER0_SKIP_HIGH(id);
void __iomem *sk_lo = hdm + CXL_HDM_DECODER0_SKIP_LOW(id);
writel(upper_32_bits(cxled->skip), sk_hi);
writel(lower_32_bits(cxled->skip), sk_lo);
}
writel(ctrl, hdm + CXL_HDM_DECODER0_CTRL_OFFSET(id));
up_read(&cxl_dpa_rwsem);
port->commit_end++;
rc = cxld_await_commit(hdm, cxld->id);
err:
if (rc) {
dev_dbg(&port->dev, "%s: error %d committing decoder\n",
dev_name(&cxld->dev), rc);
cxld->reset(cxld);
return rc;
}
cxld->flags |= CXL_DECODER_F_ENABLE;
return 0;
}
static int cxl_decoder_reset(struct cxl_decoder *cxld)
{
struct cxl_port *port = to_cxl_port(cxld->dev.parent);
struct cxl_hdm *cxlhdm = dev_get_drvdata(&port->dev);
void __iomem *hdm = cxlhdm->regs.hdm_decoder;
int id = cxld->id;
u32 ctrl;
if ((cxld->flags & CXL_DECODER_F_ENABLE) == 0)
return 0;
if (port->commit_end != id) {
dev_dbg(&port->dev,
"%s: out of order reset, expected decoder%d.%d\n",
dev_name(&cxld->dev), port->id, port->commit_end);
return -EBUSY;
}
down_read(&cxl_dpa_rwsem);
ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(id));
ctrl &= ~CXL_HDM_DECODER0_CTRL_COMMIT;
writel(ctrl, hdm + CXL_HDM_DECODER0_CTRL_OFFSET(id));
writel(0, hdm + CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(id));
writel(0, hdm + CXL_HDM_DECODER0_SIZE_LOW_OFFSET(id));
writel(0, hdm + CXL_HDM_DECODER0_BASE_HIGH_OFFSET(id));
writel(0, hdm + CXL_HDM_DECODER0_BASE_LOW_OFFSET(id));
up_read(&cxl_dpa_rwsem);
port->commit_end--;
cxld->flags &= ~CXL_DECODER_F_ENABLE;
/* Userspace is now responsible for reconfiguring this decoder */
if (is_endpoint_decoder(&cxld->dev)) {
struct cxl_endpoint_decoder *cxled;
cxled = to_cxl_endpoint_decoder(&cxld->dev);
cxled->state = CXL_DECODER_STATE_MANUAL;
}
return 0;
}
static int cxl_setup_hdm_decoder_from_dvsec(
struct cxl_port *port, struct cxl_decoder *cxld, u64 *dpa_base,
int which, struct cxl_endpoint_dvsec_info *info)
{
struct cxl_endpoint_decoder *cxled;
u64 len;
int rc;
if (!is_cxl_endpoint(port))
return -EOPNOTSUPP;
cxled = to_cxl_endpoint_decoder(&cxld->dev);
len = range_len(&info->dvsec_range[which]);
if (!len)
return -ENOENT;
cxld->target_type = CXL_DECODER_HOSTONLYMEM;
cxld->commit = NULL;
cxld->reset = NULL;
cxld->hpa_range = info->dvsec_range[which];
/*
* Set the emulated decoder as locked pending additional support to
* change the range registers at run time.
*/
cxld->flags |= CXL_DECODER_F_ENABLE | CXL_DECODER_F_LOCK;
port->commit_end = cxld->id;
rc = devm_cxl_dpa_reserve(cxled, *dpa_base, len, 0);
if (rc) {
dev_err(&port->dev,
"decoder%d.%d: Failed to reserve DPA range %#llx - %#llx\n (%d)",
port->id, cxld->id, *dpa_base, *dpa_base + len - 1, rc);
return rc;
}
*dpa_base += len;
cxled->state = CXL_DECODER_STATE_AUTO;
return 0;
}
static int init_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld,
int *target_map, void __iomem *hdm, int which,
u64 *dpa_base, struct cxl_endpoint_dvsec_info *info)
{
struct cxl_endpoint_decoder *cxled = NULL;
u64 size, base, skip, dpa_size, lo, hi;
bool committed;
u32 remainder;
int i, rc;
u32 ctrl;
union {
u64 value;
unsigned char target_id[8];
} target_list;
if (should_emulate_decoders(info))
return cxl_setup_hdm_decoder_from_dvsec(port, cxld, dpa_base,
which, info);
ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(which));
lo = readl(hdm + CXL_HDM_DECODER0_BASE_LOW_OFFSET(which));
hi = readl(hdm + CXL_HDM_DECODER0_BASE_HIGH_OFFSET(which));
base = (hi << 32) + lo;
lo = readl(hdm + CXL_HDM_DECODER0_SIZE_LOW_OFFSET(which));
hi = readl(hdm + CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(which));
size = (hi << 32) + lo;
committed = !!(ctrl & CXL_HDM_DECODER0_CTRL_COMMITTED);
cxld->commit = cxl_decoder_commit;
cxld->reset = cxl_decoder_reset;
if (!committed)
size = 0;
if (base == U64_MAX || size == U64_MAX) {
dev_warn(&port->dev, "decoder%d.%d: Invalid resource range\n",
port->id, cxld->id);
return -ENXIO;
}
if (info)
cxled = to_cxl_endpoint_decoder(&cxld->dev);
cxld->hpa_range = (struct range) {
.start = base,
.end = base + size - 1,
};
/* decoders are enabled if committed */
if (committed) {
cxld->flags |= CXL_DECODER_F_ENABLE;
if (ctrl & CXL_HDM_DECODER0_CTRL_LOCK)
cxld->flags |= CXL_DECODER_F_LOCK;
if (FIELD_GET(CXL_HDM_DECODER0_CTRL_HOSTONLY, ctrl))
cxld->target_type = CXL_DECODER_HOSTONLYMEM;
else
cxld->target_type = CXL_DECODER_DEVMEM;
if (cxld->id != port->commit_end + 1) {
dev_warn(&port->dev,
"decoder%d.%d: Committed out of order\n",
port->id, cxld->id);
return -ENXIO;
}
if (size == 0) {
dev_warn(&port->dev,
"decoder%d.%d: Committed with zero size\n",
port->id, cxld->id);
return -ENXIO;
}
port->commit_end = cxld->id;
} else {
if (cxled) {
struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
struct cxl_dev_state *cxlds = cxlmd->cxlds;
/*
* Default by devtype until a device arrives that needs
* more precision.
*/
if (cxlds->type == CXL_DEVTYPE_CLASSMEM)
cxld->target_type = CXL_DECODER_HOSTONLYMEM;
else
cxld->target_type = CXL_DECODER_DEVMEM;
} else {
/* To be overridden by region type at commit time */
cxld->target_type = CXL_DECODER_HOSTONLYMEM;
}
if (!FIELD_GET(CXL_HDM_DECODER0_CTRL_HOSTONLY, ctrl) &&
cxld->target_type == CXL_DECODER_HOSTONLYMEM) {
ctrl |= CXL_HDM_DECODER0_CTRL_HOSTONLY;
writel(ctrl, hdm + CXL_HDM_DECODER0_CTRL_OFFSET(which));
}
}
rc = eiw_to_ways(FIELD_GET(CXL_HDM_DECODER0_CTRL_IW_MASK, ctrl),
&cxld->interleave_ways);
if (rc) {
dev_warn(&port->dev,
"decoder%d.%d: Invalid interleave ways (ctrl: %#x)\n",
port->id, cxld->id, ctrl);
return rc;
}
rc = eig_to_granularity(FIELD_GET(CXL_HDM_DECODER0_CTRL_IG_MASK, ctrl),
&cxld->interleave_granularity);
if (rc)
return rc;
dev_dbg(&port->dev, "decoder%d.%d: range: %#llx-%#llx iw: %d ig: %d\n",
port->id, cxld->id, cxld->hpa_range.start, cxld->hpa_range.end,
cxld->interleave_ways, cxld->interleave_granularity);
if (!cxled) {
lo = readl(hdm + CXL_HDM_DECODER0_TL_LOW(which));
hi = readl(hdm + CXL_HDM_DECODER0_TL_HIGH(which));
target_list.value = (hi << 32) + lo;
for (i = 0; i < cxld->interleave_ways; i++)
target_map[i] = target_list.target_id[i];
return 0;
}
if (!committed)
return 0;
dpa_size = div_u64_rem(size, cxld->interleave_ways, &remainder);
if (remainder) {
dev_err(&port->dev,
"decoder%d.%d: invalid committed configuration size: %#llx ways: %d\n",
port->id, cxld->id, size, cxld->interleave_ways);
return -ENXIO;
}
lo = readl(hdm + CXL_HDM_DECODER0_SKIP_LOW(which));
hi = readl(hdm + CXL_HDM_DECODER0_SKIP_HIGH(which));
skip = (hi << 32) + lo;
rc = devm_cxl_dpa_reserve(cxled, *dpa_base + skip, dpa_size, skip);
if (rc) {
dev_err(&port->dev,
"decoder%d.%d: Failed to reserve DPA range %#llx - %#llx\n (%d)",
port->id, cxld->id, *dpa_base,
*dpa_base + dpa_size + skip - 1, rc);
return rc;
}
*dpa_base += dpa_size + skip;
cxled->state = CXL_DECODER_STATE_AUTO;
return 0;
}
static void cxl_settle_decoders(struct cxl_hdm *cxlhdm)
{
void __iomem *hdm = cxlhdm->regs.hdm_decoder;
int committed, i;
u32 ctrl;
if (!hdm)
return;
/*
* Since the register resource was recently claimed via request_region()
* be careful about trusting the "not-committed" status until the commit
* timeout has elapsed. The commit timeout is 10ms (CXL 2.0
* 8.2.5.12.20), but double it to be tolerant of any clock skew between
* host and target.
*/
for (i = 0, committed = 0; i < cxlhdm->decoder_count; i++) {
ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(i));
if (ctrl & CXL_HDM_DECODER0_CTRL_COMMITTED)
committed++;
}
/* ensure that future checks of committed can be trusted */
if (committed != cxlhdm->decoder_count)
msleep(20);
}
/**
* devm_cxl_enumerate_decoders - add decoder objects per HDM register set
* @cxlhdm: Structure to populate with HDM capabilities
* @info: cached DVSEC range register info
*/
int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm,
struct cxl_endpoint_dvsec_info *info)
{
void __iomem *hdm = cxlhdm->regs.hdm_decoder;
struct cxl_port *port = cxlhdm->port;
int i;
u64 dpa_base = 0;
cxl_settle_decoders(cxlhdm);
for (i = 0; i < cxlhdm->decoder_count; i++) {
int target_map[CXL_DECODER_MAX_INTERLEAVE] = { 0 };
int rc, target_count = cxlhdm->target_count;
struct cxl_decoder *cxld;
if (is_cxl_endpoint(port)) {
struct cxl_endpoint_decoder *cxled;
cxled = cxl_endpoint_decoder_alloc(port);
if (IS_ERR(cxled)) {
dev_warn(&port->dev,
"Failed to allocate decoder%d.%d\n",
port->id, i);
return PTR_ERR(cxled);
}
cxld = &cxled->cxld;
} else {
struct cxl_switch_decoder *cxlsd;
cxlsd = cxl_switch_decoder_alloc(port, target_count);
if (IS_ERR(cxlsd)) {
dev_warn(&port->dev,
"Failed to allocate decoder%d.%d\n",
port->id, i);
return PTR_ERR(cxlsd);
}
cxld = &cxlsd->cxld;
}
rc = init_hdm_decoder(port, cxld, target_map, hdm, i,
&dpa_base, info);
if (rc) {
dev_warn(&port->dev,
"Failed to initialize decoder%d.%d\n",
port->id, i);
put_device(&cxld->dev);
return rc;
}
rc = add_hdm_decoder(port, cxld, target_map);
if (rc) {
dev_warn(&port->dev,
"Failed to add decoder%d.%d\n", port->id, i);
return rc;
}
}
return 0;
}
EXPORT_SYMBOL_NS_GPL(devm_cxl_enumerate_decoders, CXL);
|