UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

cxl/pci: Refactor cxl_hdm_decode_init() 

With the previous refactoring of DVSEC range registers out of
cxl_hdm_decode_init(), it basically becomes a skeleton function. Squash
__cxl_hdm_decode_init() with cxl_hdm_decode_init() to simplify the code.
cxl_hdm_decode_init() now returns more error codes than just -EBUSY.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/167640367916.935665.12898404758336059003.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This commit is contained in:
Dave Jiang 2023-02-14 11:41:19 -08:00 committed by Dan Williams
parent 59c3368b2e
commit 9de321e93c
1 changed files with 54 additions and 81 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

135
drivers/cxl/core/pci.c
View File

@ -259,80 +259,6 @@ static int devm_cxl_enable_hdm(struct device *host, struct cxl_hdm *cxlhdm)
return devm_add_action_or_reset(host, disable_hdm, cxlhdm);
}
static bool __cxl_hdm_decode_init(struct cxl_dev_state *cxlds,
struct cxl_hdm *cxlhdm,
struct cxl_endpoint_dvsec_info *info)
{
void __iomem *hdm = cxlhdm->regs.hdm_decoder;
struct cxl_port *port = cxlhdm->port;
struct device *dev = cxlds->dev;
struct cxl_port *root;
int i, rc, allowed;
u32 global_ctrl;
global_ctrl = readl(hdm + CXL_HDM_DECODER_CTRL_OFFSET);
/*
* If the HDM Decoder Capability is already enabled then assume
* that some other agent like platform firmware set it up.
*/
if (global_ctrl & CXL_HDM_DECODER_ENABLE) {
rc = devm_cxl_enable_mem(&port->dev, cxlds);
if (rc)
return false;
return true;
}
root = to_cxl_port(port->dev.parent);
while (!is_cxl_root(root) && is_cxl_port(root->dev.parent))
root = to_cxl_port(root->dev.parent);
if (!is_cxl_root(root)) {
dev_err(dev, "Failed to acquire root port for HDM enable\n");
return false;
}
for (i = 0, allowed = 0; info->mem_enabled && i < info->ranges; i++) {
struct device *cxld_dev;
cxld_dev = device_find_child(&root->dev, &info->dvsec_range[i],
dvsec_range_allowed);
if (!cxld_dev) {
dev_dbg(dev, "DVSEC Range%d denied by platform\n", i);
continue;
}
dev_dbg(dev, "DVSEC Range%d allowed by platform\n", i);
put_device(cxld_dev);
allowed++;
}
if (!allowed) {
cxl_set_mem_enable(cxlds, 0);
info->mem_enabled = 0;
}
/*
* Per CXL 2.0 Section 8.1.3.8.3 and 8.1.3.8.4 DVSEC CXL Range 1 Base
* [High,Low] when HDM operation is enabled the range register values
* are ignored by the device, but the spec also recommends matching the
* DVSEC Range 1,2 to HDM Decoder Range 0,1. So, non-zero info->ranges
* are expected even though Linux does not require or maintain that
* match. If at least one DVSEC range is enabled and allowed, skip HDM
* Decoder Capability Enable.
*/
if (info->mem_enabled)
return false;
rc = devm_cxl_enable_hdm(&port->dev, cxlhdm);
if (rc)
return false;
rc = devm_cxl_enable_mem(&port->dev, cxlds);
if (rc)
return false;
return true;
}
int cxl_dvsec_rr_decode(struct device *dev, int d,
struct cxl_endpoint_dvsec_info *info)
{
@ -447,19 +373,66 @@ EXPORT_SYMBOL_NS_GPL(cxl_dvsec_rr_decode, CXL);
int cxl_hdm_decode_init(struct cxl_dev_state *cxlds, struct cxl_hdm *cxlhdm,
struct cxl_endpoint_dvsec_info *info)
{
void __iomem *hdm = cxlhdm->regs.hdm_decoder;
struct cxl_port *port = cxlhdm->port;
struct device *dev = cxlds->dev;
struct cxl_port *root;
int i, rc, allowed;
u32 global_ctrl;
global_ctrl = readl(hdm + CXL_HDM_DECODER_CTRL_OFFSET);
/*
* If DVSEC ranges are being used instead of HDM decoder registers there
* is no use in trying to manage those.
* If the HDM Decoder Capability is already enabled then assume
* that some other agent like platform firmware set it up.
*/
if (!__cxl_hdm_decode_init(cxlds, cxlhdm, info)) {
dev_err(dev,
"Legacy range registers configuration prevents HDM operation.\n");
return -EBUSY;
if (global_ctrl & CXL_HDM_DECODER_ENABLE)
return devm_cxl_enable_mem(&port->dev, cxlds);
root = to_cxl_port(port->dev.parent);
while (!is_cxl_root(root) && is_cxl_port(root->dev.parent))
root = to_cxl_port(root->dev.parent);
if (!is_cxl_root(root)) {
dev_err(dev, "Failed to acquire root port for HDM enable\n");
return -ENODEV;
}
return 0;
for (i = 0, allowed = 0; info->mem_enabled && i < info->ranges; i++) {
struct device *cxld_dev;
cxld_dev = device_find_child(&root->dev, &info->dvsec_range[i],
dvsec_range_allowed);
if (!cxld_dev) {
dev_dbg(dev, "DVSEC Range%d denied by platform\n", i);
continue;
}
dev_dbg(dev, "DVSEC Range%d allowed by platform\n", i);
put_device(cxld_dev);
allowed++;
}
if (!allowed) {
cxl_set_mem_enable(cxlds, 0);
info->mem_enabled = 0;
}
/*
* Per CXL 2.0 Section 8.1.3.8.3 and 8.1.3.8.4 DVSEC CXL Range 1 Base
* [High,Low] when HDM operation is enabled the range register values
* are ignored by the device, but the spec also recommends matching the
* DVSEC Range 1,2 to HDM Decoder Range 0,1. So, non-zero info->ranges
* are expected even though Linux does not require or maintain that
* match. If at least one DVSEC range is enabled and allowed, skip HDM
* Decoder Capability Enable.
*/
if (info->mem_enabled)
return -EBUSY;
rc = devm_cxl_enable_hdm(&port->dev, cxlhdm);
if (rc)
return rc;
return devm_cxl_enable_mem(&port->dev, cxlds);
}
EXPORT_SYMBOL_NS_GPL(cxl_hdm_decode_init, CXL);