On 24-06-2025 15:58, Poosa, Karthik wrote:
On 29-05-2025 16:46, Badal Nilawar wrote:Instead of indefinite retry, can you retries with count, ~3 times, after which we can return failure.Add the API xe_pm_vrsr_enable to initialize the VRSR feature, requesting AUX power limit and PERST# assertion delay. V2: Add retry mechanism while requesting AUX power limit Signed-off-by: Badal Nilawar <badal.nilawar@xxxxxxxxx> Signed-off-by: Anshuman Gupta <anshuman.gupta@xxxxxxxxx> --- drivers/gpu/drm/xe/xe_device_types.h | 1 + drivers/gpu/drm/xe/xe_pcode_api.h | 7 ++ drivers/gpu/drm/xe/xe_pm.c | 105 ++++++++++++++++++++++++++- drivers/gpu/drm/xe/xe_pm.h | 1 + 4 files changed, 113 insertions(+), 1 deletion(-)diff --git a/drivers/gpu/drm/xe/xe_device_types.h b/drivers/gpu/drm/xe/xe_device_types.hindex 3a15b3a252fd..5f9a1a358468 100644 --- a/drivers/gpu/drm/xe/xe_device_types.h +++ b/drivers/gpu/drm/xe/xe_device_types.h @@ -7,6 +7,7 @@ #define _XE_DEVICE_TYPES_H_ #include <linux/pci.h> +#include <linux/pci-acpi.h> #include <drm/drm_device.h> #include <drm/drm_file.h>diff --git a/drivers/gpu/drm/xe/xe_pcode_api.h b/drivers/gpu/drm/xe/xe_pcode_api.hindex 127d4d26c4cf..f54ef03799d4 100644 --- a/drivers/gpu/drm/xe/xe_pcode_api.h +++ b/drivers/gpu/drm/xe/xe_pcode_api.h @@ -43,6 +43,13 @@#define POWER_SETUP_I1_SHIFT 6 /* 10.6 fixed point format */#define POWER_SETUP_I1_DATA_MASK REG_GENMASK(15, 0) +#define PCODE_D3_VRAM_SELF_REFRESH 0x71 +#define PCODE_D3_VRSR_SC_DISABLE 0x0 +#define PCODE_D3_VRSR_SC_ENABLE 0x1 +#define PCODE_D3_VRSR_SC_AUX_PL_AND_PERST_DELAY 0x2 +#define POWER_D3_VRSR_PERST_MASK REG_GENMASK(31, 16) +#define POWER_D3_VRSR_AUX_PL_MASK REG_GENMASK(15, 0) + #define PCODE_FREQUENCY_CONFIG 0x6e /* Frequency Config Sub Commands (param1) */ #define PCODE_MBOX_FC_SC_READ_FUSED_P0 0x0 diff --git a/drivers/gpu/drm/xe/xe_pm.c b/drivers/gpu/drm/xe/xe_pm.c index c9395e62d21d..278f2eeeaab6 100644 --- a/drivers/gpu/drm/xe/xe_pm.c +++ b/drivers/gpu/drm/xe/xe_pm.c @@ -5,6 +5,7 @@ #include "xe_pm.h" +#include <linux/delay.h> #include <linux/fault-inject.h> #include <linux/pm_runtime.h> #include <linux/suspend.h> @@ -23,6 +24,7 @@ #include "xe_guc.h" #include "xe_irq.h" #include "xe_mmio.h" +#include "xe_pcode_api.h" #include "xe_pcode.h" #include "xe_pxp.h" #include "xe_trace.h"@@ -260,6 +262,107 @@ static bool xe_pm_vrsr_capable(struct xe_device *xe)return val & VRAM_SR_SUPPORTED; } +static int pci_acpi_aux_power_setup(struct xe_device *xe) +{ + struct xe_tile *root_tile = xe_device_get_root_tile(xe); + struct pci_dev *pdev = to_pci_dev(xe->drm.dev); + struct pci_dev *root_pdev; + int ret; + u32 uval; + u32 aux_pwr_limit; + u32 retry_interval; + u32 perst_delay; + + root_pdev = pcie_find_root_port(pdev); + if (!root_pdev) + return -EINVAL; ++ ret = xe_pcode_read(root_tile, PCODE_MBOX(PCODE_D3_VRAM_SELF_REFRESH,+ PCODE_D3_VRSR_SC_AUX_PL_AND_PERST_DELAY, 0), + &uval, NULL); + + if (ret) + return ret; + + aux_pwr_limit = REG_FIELD_GET(POWER_D3_VRSR_AUX_PL_MASK, uval); + perst_delay = REG_FIELD_GET(POWER_D3_VRSR_PERST_MASK, uval); + + drm_dbg(&xe->drm, "Aux Power limit = %d mW\n", aux_pwr_limit);+ drm_dbg(&xe->drm, "PERST# Assertion delay = %d microseconds\n", perst_delay);+ +retry:+ ret = pci_acpi_request_d3cold_aux_power(root_pdev, aux_pwr_limit, &retry_interval);+ + if (ret == -EAGAIN) {+ drm_warn(&xe->drm, "D3cold Aux Power request needs retry interval: %d seconds\n",+ retry_interval); + msleep(retry_interval * 1000); + goto retry;
Retry count is not needed because as per PCI firmware specifications, section 4.6.10 Rev 3.3. Firmware is not permitted to return a value in this range more than once for each _DSM instance (located within the ACPI namespace of a single downstream port DeviceObject), unless there is a subsequent invocation of this function before the previously returned retry interval has expired.
+ } + + if (ret) + return ret; + + ret = pci_acpi_add_perst_assertion_delay(root_pdev, perst_delay); + + return ret; +} + +static void xe_pm_vrsr_init(struct xe_device *xe) +{ + int ret; + + /* Check if platform support D3Cold VRSR */This can be rephrased to, "Check if Xe should support VRSR for the platform."
Here with has_vrsr we are checking if DGFX platform support VRSR or not. If supported, VRSR will be enabled in Xe kmd.
I think let's keep the comment as it is.
+ if (!xe->info.has_vrsr)Can you add a comment here also, viz "Check if GPU firmware supports VRSR"+ return; +
Sure, I will add.
+ if (!xe_pm_vrsr_capable(xe)) + return; + + /*+ * If the VRSR initialization fails, the device will proceed with the regular+ * D3Cold flow + */ + ret = pci_acpi_aux_power_setup(xe); + if (ret) { + drm_info(&xe->drm, "VRSR capable: No\n"); + return; + } + + xe->d3cold.vrsr_capable = true; + drm_info(&xe->drm, "VRSR capable: Yes\n"); +} + +/** + * xe_pm_vrsr_enable - Enable VRAM self refreshas this function does both enable & disable VRSR, this can be renamed to xe_pm_set_vrsr(xe, flag)
IMO, _vrsr_enable() is a more suitable name than _set_vrsr. Since the subsequent patches don't involve disabling VRSR, I can remove the flag and retain only the code for enabling it. Note that VRSR is internally disabled by pcode upon exiting D3Cold. Therefore, in subsequent patches, VRSR is re-enabled each time before entering D3Cold.
Thanks, Badal
+ * @xe: The xe device. + * @enable: true: Enable, false: Disable + * + * This function enables the VRSR feature in D3Cold path. + * + * Return: It returns 0 on success and errno on failure. + */ +int xe_pm_vrsr_enable(struct xe_device *xe, bool enable) +{ + struct xe_tile *root_tile = xe_device_get_root_tile(xe); + int ret; + u32 uval = 0; + + if (!xe->d3cold.vrsr_capable) + return -ENXIO; + + drm_dbg(&xe->drm, "%s VRSR\n", enable ? "Enabling" : "Disabling"); + + if (enable)+ ret = xe_pcode_write(root_tile, PCODE_MBOX(PCODE_D3_VRAM_SELF_REFRESH,+ PCODE_D3_VRSR_SC_ENABLE, 0), uval); + else+ ret = xe_pcode_write(root_tile, PCODE_MBOX(PCODE_D3_VRAM_SELF_REFRESH,+ PCODE_D3_VRSR_SC_DISABLE, 0), uval); + + return ret; +} + static void xe_pm_runtime_init(struct xe_device *xe) { struct device *dev = xe->drm.dev; @@ -374,7 +477,7 @@ int xe_pm_init(struct xe_device *xe) err = xe_pm_set_vram_threshold(xe, vram_threshold); if (err) goto err_unregister; - xe->d3cold.vrsr_capable = xe_pm_vrsr_capable(xe); + xe_pm_vrsr_init(xe); } xe_pm_runtime_init(xe); diff --git a/drivers/gpu/drm/xe/xe_pm.h b/drivers/gpu/drm/xe/xe_pm.h index 59678b310e55..ba550281b130 100644 --- a/drivers/gpu/drm/xe/xe_pm.h +++ b/drivers/gpu/drm/xe/xe_pm.h @@ -35,4 +35,5 @@ bool xe_rpm_reclaim_safe(const struct xe_device *xe); struct task_struct *xe_pm_read_callback_task(struct xe_device *xe); int xe_pm_module_init(void); +int xe_pm_vrsr_enable(struct xe_device *xe, bool enable); #endif
