platform/x86/intel/pmc: Allow reenabling LTRs

Commit 804951203aa5 ("platform/x86:intel/pmc: Combine core_init() and
core_configure()") caused a network performance regression due to the GBE
LTR ignore that it added during probe. The fix will move the ignore to
occur at suspend-time (so as to not affect suspend power). This will
require the ability to enable the LTR again on resume. Modify
pmc_core_send_ltr_ignore() to allow enabling an LTR.

Fixes: 804951203aa5 ("platform/x86:intel/pmc: Combine core_init() and core_configure()")
Signed-off-by: "David E. Box" <david.e.box@linux.intel.com>
Link: https://lore.kernel.org/r/20231223032548.1680738-5-david.e.box@linux.intel.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

6 files changed, 11 insertions, 8 deletions

diff --git a/drivers/platform/x86/intel/pmc/adl.c b/drivers/platform/x86/intel/pmc/adl.c
index 5006008e01be..a887c388cf16 100644
--- a/drivers/platform/x86/intel/pmc/adl.c
+++ b/drivers/platform/x86/intel/pmc/adl.c
@@ -323,7 +323,7 @@ int adl_core_init(struct pmc_dev *pmcdev)
 	 * when a cable is attached. Tell the PMC to ignore it.
 	 */
 	dev_dbg(&pmcdev->pdev->dev, "ignoring GBE LTR\n");
-	pmc_core_send_ltr_ignore(pmcdev, 3);
+	pmc_core_send_ltr_ignore(pmcdev, 3, 1);
 
 	return 0;
 }
diff --git a/drivers/platform/x86/intel/pmc/cnp.c b/drivers/platform/x86/intel/pmc/cnp.c
index 420aaa1d7c76..10498204962c 100644
--- a/drivers/platform/x86/intel/pmc/cnp.c
+++ b/drivers/platform/x86/intel/pmc/cnp.c
@@ -218,7 +218,7 @@ int cnp_core_init(struct pmc_dev *pmcdev)
 	 * when a cable is attached. Tell the PMC to ignore it.
 	 */
 	dev_dbg(&pmcdev->pdev->dev, "ignoring GBE LTR\n");
-	pmc_core_send_ltr_ignore(pmcdev, 3);
+	pmc_core_send_ltr_ignore(pmcdev, 3, 1);
 
 	return 0;
 }
diff --git a/drivers/platform/x86/intel/pmc/core.c b/drivers/platform/x86/intel/pmc/core.c
index 5ab470d87ad7..022afb97d531 100644
--- a/drivers/platform/x86/intel/pmc/core.c
+++ b/drivers/platform/x86/intel/pmc/core.c
@@ -460,7 +460,7 @@ out_unlock:
 }
 DEFINE_SHOW_ATTRIBUTE(pmc_core_pll);
 
-int pmc_core_send_ltr_ignore(struct pmc_dev *pmcdev, u32 value)
+int pmc_core_send_ltr_ignore(struct pmc_dev *pmcdev, u32 value, int ignore)
 {
 	struct pmc *pmc;
 	const struct pmc_reg_map *map;
@@ -498,7 +498,10 @@ int pmc_core_send_ltr_ignore(struct pmc_dev *pmcdev, u32 value)
 	mutex_lock(&pmcdev->lock);
 
 	reg = pmc_core_reg_read(pmc, map->ltr_ignore_offset);
-	reg |= BIT(ltr_index);
+	if (ignore)
+		reg |= BIT(ltr_index);
+	else
+		reg &= ~BIT(ltr_index);
 	pmc_core_reg_write(pmc, map->ltr_ignore_offset, reg);
 
 	mutex_unlock(&pmcdev->lock);
@@ -521,7 +524,7 @@ static ssize_t pmc_core_ltr_ignore_write(struct file *file,
 	if (err)
 		return err;
 
-	err = pmc_core_send_ltr_ignore(pmcdev, value);
+	err = pmc_core_send_ltr_ignore(pmcdev, value, 1);
 
 	return err == 0 ? count : err;
 }
diff --git a/drivers/platform/x86/intel/pmc/core.h b/drivers/platform/x86/intel/pmc/core.h
index 38d888e3afa6..71ba7d691d69 100644
--- a/drivers/platform/x86/intel/pmc/core.h
+++ b/drivers/platform/x86/intel/pmc/core.h
@@ -488,7 +488,7 @@ extern const struct pmc_bit_map *mtl_ioem_lpm_maps[];
 extern const struct pmc_reg_map mtl_ioem_reg_map;
 
 extern void pmc_core_get_tgl_lpm_reqs(struct platform_device *pdev);
-extern int pmc_core_send_ltr_ignore(struct pmc_dev *pmcdev, u32 value);
+int pmc_core_send_ltr_ignore(struct pmc_dev *pmcdev, u32 value, int ignore);
 
 int pmc_core_resume_common(struct pmc_dev *pmcdev);
 int get_primary_reg_base(struct pmc *pmc);
diff --git a/drivers/platform/x86/intel/pmc/mtl.c b/drivers/platform/x86/intel/pmc/mtl.c
index 2204bc666980..71dc11811e11 100644
--- a/drivers/platform/x86/intel/pmc/mtl.c
+++ b/drivers/platform/x86/intel/pmc/mtl.c
@@ -1006,7 +1006,7 @@ int mtl_core_init(struct pmc_dev *pmcdev)
 	 * when a cable is attached. Tell the PMC to ignore it.
 	 */
 	dev_dbg(&pmcdev->pdev->dev, "ignoring GBE LTR\n");
-	pmc_core_send_ltr_ignore(pmcdev, 3);
+	pmc_core_send_ltr_ignore(pmcdev, 3, 1);
 
 	return 0;
 }
diff --git a/drivers/platform/x86/intel/pmc/tgl.c b/drivers/platform/x86/intel/pmc/tgl.c
index 2449940102db..078263db24c7 100644
--- a/drivers/platform/x86/intel/pmc/tgl.c
+++ b/drivers/platform/x86/intel/pmc/tgl.c
@@ -268,7 +268,7 @@ int tgl_core_init(struct pmc_dev *pmcdev)
 	 * when a cable is attached. Tell the PMC to ignore it.
 	 */
 	dev_dbg(&pmcdev->pdev->dev, "ignoring GBE LTR\n");
-	pmc_core_send_ltr_ignore(pmcdev, 3);
+	pmc_core_send_ltr_ignore(pmcdev, 3, 1);
 
 	return 0;
 }