From: "Saheed O. Bolarinwa" <refactormyself@gmail.com>
To: helgaas@kernel.org
Cc: "Saheed O. Bolarinwa" <refactormyself@gmail.com>,
linux-kernel-mentees@lists.linuxfoundation.org
Subject: [Linux-kernel-mentees] [RFC PATCH v5 01/23] PCI: Migrate ASPM info from struct pcie_link_state to struct pci_dev
Date: Sat, 22 Aug 2020 22:03:36 +0200 [thread overview]
Message-ID: <20200822200358.252967-2-refactormyself@gmail.com> (raw)
In-Reply-To: <20200822200358.252967-1-refactormyself@gmail.com>
pcie_get_aspm_reg() reads LNKCAP to learn whether the device supports
ASPM L0s and/or L1 and L1 substates.
If we cache the entire LNKCAP word early enough, we may be able to
use it in other places that read LNKCAP, e.g. pcie_get_speed_cap(),
pcie_get_width_cap(), pcie_init(), etc.
- Add struct pci_dev.lnkcap (u32)
- Read PCI_EXP_LNKCAP in set_pcie_port_type() and save it
in pci_dev.lnkcap
- Use pdev->lnkcap instead of reading PCI_EXP_LNKCAP
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
---
drivers/pci/pcie/aspm.c | 7 ++-----
drivers/pci/probe.c | 1 +
include/linux/pci.h | 1 +
3 files changed, 4 insertions(+), 5 deletions(-)
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index b17e5ffd31b1..3ada61828014 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -177,15 +177,13 @@ static void pcie_set_clkpm(struct pcie_link_state *link, int enable)
static void pcie_clkpm_cap_init(struct pcie_link_state *link, int blacklist)
{
int capable = 1, enabled = 1;
- u32 reg32;
u16 reg16;
struct pci_dev *child;
struct pci_bus *linkbus = link->pdev->subordinate;
/* All functions should have the same cap and state, take the worst */
list_for_each_entry(child, &linkbus->devices, bus_list) {
- pcie_capability_read_dword(child, PCI_EXP_LNKCAP, ®32);
- if (!(reg32 & PCI_EXP_LNKCAP_CLKPM)) {
+ if (!(child->lnkcap & PCI_EXP_LNKCAP_CLKPM)) {
capable = 0;
enabled = 0;
break;
@@ -397,9 +395,8 @@ static void pcie_get_aspm_reg(struct pci_dev *pdev,
struct aspm_register_info *info)
{
u16 reg16;
- u32 reg32;
+ u32 reg32 = pdev->lnkcap;
- pcie_capability_read_dword(pdev, PCI_EXP_LNKCAP, ®32);
info->support = (reg32 & PCI_EXP_LNKCAP_ASPMS) >> 10;
info->latency_encoding_l0s = (reg32 & PCI_EXP_LNKCAP_L0SEL) >> 12;
info->latency_encoding_l1 = (reg32 & PCI_EXP_LNKCAP_L1EL) >> 15;
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 2f66988cea25..6cae7230f3b5 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1480,6 +1480,7 @@ void set_pcie_port_type(struct pci_dev *pdev)
pdev->pcie_flags_reg = reg16;
pci_read_config_word(pdev, pos + PCI_EXP_DEVCAP, ®16);
pdev->pcie_mpss = reg16 & PCI_EXP_DEVCAP_PAYLOAD;
+ pcie_capability_read_dword(pdev, PCI_EXP_LNKCAP, &pdev->lnkcap);
parent = pci_upstream_bridge(pdev);
if (!parent)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 34c1c4f45288..3d30d3650ac9 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -375,6 +375,7 @@ struct pci_dev {
bit manually */
unsigned int d3_delay; /* D3->D0 transition time in ms */
unsigned int d3cold_delay; /* D3cold->D0 transition time in ms */
+ u32 lnkcap; /* Link Capabilities */
#ifdef CONFIG_PCIEASPM
struct pcie_link_state *link_state; /* ASPM link state */
--
2.18.4
_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees
next prev parent reply other threads:[~2020-08-22 21:03 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-22 20:03 [Linux-kernel-mentees] [RFC PATCH v5 00/23] Remove struct pcie_link_state and aspm_register_info Saheed O. Bolarinwa
2020-08-22 20:03 ` Saheed O. Bolarinwa [this message]
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 02/23] PCI: Add l1ss_cap and l1ss_cap_ptr to struct pci_dev Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 03/23] PCI: Rework calc_l*_latency() to take a pci_dev * Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 04/23] PCI: Compute aspm_register_info.support directly Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 05/23] PCI: Read value of aspm_register_info.l1ss_ctl1 directly Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 06/23] PCI: Replace aspm_register_info.l1ss_cap* with their pci_dev version Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 07/23] PCI: Compute aspm_register_info.enable directly Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 08/23] PCI: Remove unused aspm_calc_l1ss_info() arguments Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 09/23] PCI: Remove pcie_get_aspm_reg() and struct aspm_register_info Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 10/23] PCI: Relocate call to aspm_calc_l1ss_info Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 11/23] PCI: Rework and Rename aspm_calc_l1ss_info() Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 12/23] PCI: Add ASPM and CLOCK PM states to struct pci_dev Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 13/23] PCI: Initialise and Update values of pci_dev's PCIe link info Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 14/23] PCI: Change Return and Argument values from pcie_link_state to pci_dev Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 15/23] PCI: Replace pcie_link_state based device list with a pci_dev one Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 16/23] PCI: Remove Exit latencies from struct pcie_link_state Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 17/23] PCI: Remove .clkpm_* " Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 18/23] PCI: Remove .aspm_* " Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 19/23] PCI: Remove .parent " Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 20/23] PCI: Remove .root " Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 21/23] PCI: Remove .downstream " Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 22/23] PCI: Remove .pdev " Saheed O. Bolarinwa
2020-08-22 20:03 ` [Linux-kernel-mentees] [RFC PATCH v5 23/23] PCI: Remove " Saheed O. Bolarinwa
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200822200358.252967-2-refactormyself@gmail.com \
--to=refactormyself@gmail.com \
--cc=helgaas@kernel.org \
--cc=linux-kernel-mentees@lists.linuxfoundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).