This patch adds common helpers to issue power commands, poll transitions, and validate domain state, then wires them into the L2 on/off paths.
The L2 power-on sequence now delegates control of the SHADER and TILER domains to the MCU when allowed, while the L2 itself is never delegated. On power-off, dependent domains beneath the L2 are checked, and if necessary, retracted and powered down to maintain proper domain ordering. Reviewed-by: Steven Price <[email protected]> Signed-off-by: Karunika Choo <[email protected]> --- v4: * removed extra brackets. * Picked up R-b from Steve. v2: * Updated GENMASK to GENMASK_U64 to address kernel test robot warnings for 32-bit systems. * Removed panthor_pwr_read_status() in favour of a simple gpu_read64() operation on the PWR_STATUS register. * Renamed panthor_pwr_info_show() to panthor_pwr_debug_info_show() for more clarity. * Added additional WARN_ON for an invalid domain when requesting power domain transition. * Made panthor_pwr_domain_transition()'s expected val logic more readable and clearer. * Wait on domain power transition instead of failing the operation. * Fixed inconsistent error return value vs kerneldoc. * Removed confusing drm_dbg in delegate_domain() in favor of a comment. * Add unwind to panthor_pwr_delegate_domains(). * Moved child domain handling logic from panthor_pwr_l2_power_off() into panthor_pwr_domain_force_off(). * Added additional clarification regarding delegation and retraction of power domains. * Minor formatting and readability changes and remove unnecessary checks. --- drivers/gpu/drm/panthor/panthor_pwr.c | 378 +++++++++++++++++++++++++ drivers/gpu/drm/panthor/panthor_pwr.h | 4 + drivers/gpu/drm/panthor/panthor_regs.h | 1 + 3 files changed, 383 insertions(+) diff --git a/drivers/gpu/drm/panthor/panthor_pwr.c b/drivers/gpu/drm/panthor/panthor_pwr.c index 66dc72b29116..6dff5daf77d2 100644 --- a/drivers/gpu/drm/panthor/panthor_pwr.c +++ b/drivers/gpu/drm/panthor/panthor_pwr.c @@ -24,6 +24,14 @@ PWR_IRQ_COMMAND_NOT_ALLOWED | \ PWR_IRQ_COMMAND_INVALID) +#define PWR_ALL_CORES_MASK GENMASK_U64(63, 0) + +#define PWR_DOMAIN_MAX_BITS 16 + +#define PWR_TRANSITION_TIMEOUT_US (2ULL * USEC_PER_SEC) + +#define PWR_RETRACT_TIMEOUT_US (2ULL * USEC_PER_MSEC) + /** * struct panthor_pwr - PWR_CONTROL block management data. */ @@ -60,6 +68,323 @@ static void panthor_pwr_irq_handler(struct panthor_device *ptdev, u32 status) } PANTHOR_IRQ_HANDLER(pwr, PWR, panthor_pwr_irq_handler); +static void panthor_pwr_write_command(struct panthor_device *ptdev, u32 command, u64 args) +{ + if (args) + gpu_write64(ptdev, PWR_CMDARG, args); + + gpu_write(ptdev, PWR_COMMAND, command); +} + +static const char *get_domain_name(u8 domain) +{ + switch (domain) { + case PWR_COMMAND_DOMAIN_L2: + return "L2"; + case PWR_COMMAND_DOMAIN_TILER: + return "Tiler"; + case PWR_COMMAND_DOMAIN_SHADER: + return "Shader"; + case PWR_COMMAND_DOMAIN_BASE: + return "Base"; + case PWR_COMMAND_DOMAIN_STACK: + return "Stack"; + } + return "Unknown"; +} + +static u32 get_domain_base(u8 domain) +{ + switch (domain) { + case PWR_COMMAND_DOMAIN_L2: + return PWR_L2_PRESENT; + case PWR_COMMAND_DOMAIN_TILER: + return PWR_TILER_PRESENT; + case PWR_COMMAND_DOMAIN_SHADER: + return PWR_SHADER_PRESENT; + case PWR_COMMAND_DOMAIN_BASE: + return PWR_BASE_PRESENT; + case PWR_COMMAND_DOMAIN_STACK: + return PWR_STACK_PRESENT; + } + return 0; +} + +static u32 get_domain_ready_reg(u32 domain) +{ + return get_domain_base(domain) + (PWR_L2_READY - PWR_L2_PRESENT); +} + +static u32 get_domain_pwrtrans_reg(u32 domain) +{ + return get_domain_base(domain) + (PWR_L2_PWRTRANS - PWR_L2_PRESENT); +} + +static bool is_valid_domain(u32 domain) +{ + return get_domain_base(domain) != 0; +} + +static bool has_rtu(struct panthor_device *ptdev) +{ + return ptdev->gpu_info.gpu_features & GPU_FEATURES_RAY_TRAVERSAL; +} + +static u8 get_domain_subdomain(struct panthor_device *ptdev, u32 domain) +{ + if (domain == PWR_COMMAND_DOMAIN_SHADER && has_rtu(ptdev)) + return PWR_COMMAND_SUBDOMAIN_RTU; + + return 0; +} + +static int panthor_pwr_domain_wait_transition(struct panthor_device *ptdev, u32 domain, + u32 timeout_us) +{ + u32 pwrtrans_reg = get_domain_pwrtrans_reg(domain); + u64 val; + int ret = 0; + + ret = gpu_read64_poll_timeout(ptdev, pwrtrans_reg, val, !(PWR_ALL_CORES_MASK & val), 100, + timeout_us); + if (ret) { + drm_err(&ptdev->base, "%s domain power in transition, pwrtrans(0x%llx)", + get_domain_name(domain), val); + return ret; + } + + return 0; +} + +static void panthor_pwr_debug_info_show(struct panthor_device *ptdev) +{ + drm_info(&ptdev->base, "GPU_FEATURES: 0x%016llx", gpu_read64(ptdev, GPU_FEATURES)); + drm_info(&ptdev->base, "PWR_STATUS: 0x%016llx", gpu_read64(ptdev, PWR_STATUS)); + drm_info(&ptdev->base, "L2_PRESENT: 0x%016llx", gpu_read64(ptdev, PWR_L2_PRESENT)); + drm_info(&ptdev->base, "L2_PWRTRANS: 0x%016llx", gpu_read64(ptdev, PWR_L2_PWRTRANS)); + drm_info(&ptdev->base, "L2_READY: 0x%016llx", gpu_read64(ptdev, PWR_L2_READY)); + drm_info(&ptdev->base, "TILER_PRESENT: 0x%016llx", gpu_read64(ptdev, PWR_TILER_PRESENT)); + drm_info(&ptdev->base, "TILER_PWRTRANS: 0x%016llx", gpu_read64(ptdev, PWR_TILER_PWRTRANS)); + drm_info(&ptdev->base, "TILER_READY: 0x%016llx", gpu_read64(ptdev, PWR_TILER_READY)); + drm_info(&ptdev->base, "SHADER_PRESENT: 0x%016llx", gpu_read64(ptdev, PWR_SHADER_PRESENT)); + drm_info(&ptdev->base, "SHADER_PWRTRANS: 0x%016llx", gpu_read64(ptdev, PWR_SHADER_PWRTRANS)); + drm_info(&ptdev->base, "SHADER_READY: 0x%016llx", gpu_read64(ptdev, PWR_SHADER_READY)); +} + +static int panthor_pwr_domain_transition(struct panthor_device *ptdev, u32 cmd, u32 domain, + u64 mask, u32 timeout_us) +{ + u32 ready_reg = get_domain_ready_reg(domain); + u32 pwr_cmd = PWR_COMMAND_DEF(cmd, domain, get_domain_subdomain(ptdev, domain)); + u64 expected_val = 0; + u64 val; + int ret = 0; + + if (drm_WARN_ON(&ptdev->base, !is_valid_domain(domain))) + return -EINVAL; + + switch (cmd) { + case PWR_COMMAND_POWER_DOWN: + expected_val = 0; + break; + case PWR_COMMAND_POWER_UP: + expected_val = mask; + break; + default: + drm_err(&ptdev->base, "Invalid power domain transition command (0x%x)", cmd); + return -EINVAL; + } + + ret = panthor_pwr_domain_wait_transition(ptdev, domain, timeout_us); + if (ret) + return ret; + + /* domain already in target state, return early */ + if ((gpu_read64(ptdev, ready_reg) & mask) == expected_val) + return 0; + + panthor_pwr_write_command(ptdev, pwr_cmd, mask); + + ret = gpu_read64_poll_timeout(ptdev, ready_reg, val, (mask & val) == expected_val, 100, + timeout_us); + if (ret) { + drm_err(&ptdev->base, + "timeout waiting on %s power domain transition, cmd(0x%x), arg(0x%llx)", + get_domain_name(domain), pwr_cmd, mask); + panthor_pwr_debug_info_show(ptdev); + return ret; + } + + return 0; +} + +#define panthor_pwr_domain_power_off(__ptdev, __domain, __mask, __timeout_us) \ + panthor_pwr_domain_transition(__ptdev, PWR_COMMAND_POWER_DOWN, __domain, __mask, \ + __timeout_us) + +#define panthor_pwr_domain_power_on(__ptdev, __domain, __mask, __timeout_us) \ + panthor_pwr_domain_transition(__ptdev, PWR_COMMAND_POWER_UP, __domain, __mask, __timeout_us) + +/** + * retract_domain() - Retract control of a domain from MCU + * @ptdev: Device. + * @domain: Domain to retract the control + * + * Retracting L2 domain is not expected since it won't be delegated. + * + * Return: 0 on success or retracted already. + * -EPERM if domain is L2. + * A negative error code otherwise. + */ +static int retract_domain(struct panthor_device *ptdev, u32 domain) +{ + const u32 pwr_cmd = PWR_COMMAND_DEF(PWR_COMMAND_RETRACT, domain, 0); + const u64 pwr_status = gpu_read64(ptdev, PWR_STATUS); + const u64 delegated_mask = PWR_STATUS_DOMAIN_DELEGATED(domain); + const u64 allow_mask = PWR_STATUS_DOMAIN_ALLOWED(domain); + u64 val; + int ret; + + if (drm_WARN_ON(&ptdev->base, domain == PWR_COMMAND_DOMAIN_L2)) + return -EPERM; + + ret = gpu_read64_poll_timeout(ptdev, PWR_STATUS, val, !(PWR_STATUS_RETRACT_PENDING & val), + 0, PWR_RETRACT_TIMEOUT_US); + if (ret) { + drm_err(&ptdev->base, "%s domain retract pending", get_domain_name(domain)); + return ret; + } + + if (!(pwr_status & delegated_mask)) { + drm_dbg(&ptdev->base, "%s domain already retracted", get_domain_name(domain)); + return 0; + } + + panthor_pwr_write_command(ptdev, pwr_cmd, 0); + + /* + * On successful retraction + * allow-flag will be set with delegated-flag being cleared. + */ + ret = gpu_read64_poll_timeout(ptdev, PWR_STATUS, val, + ((delegated_mask | allow_mask) & val) == allow_mask, 10, + PWR_TRANSITION_TIMEOUT_US); + if (ret) { + drm_err(&ptdev->base, "Retracting %s domain timeout, cmd(0x%x)", + get_domain_name(domain), pwr_cmd); + return ret; + } + + return 0; +} + +/** + * delegate_domain() - Delegate control of a domain to MCU + * @ptdev: Device. + * @domain: Domain to delegate the control + * + * Delegating L2 domain is prohibited. + * + * Return: + * * 0 on success or delegated already. + * * -EPERM if domain is L2. + * * A negative error code otherwise. + */ +static int delegate_domain(struct panthor_device *ptdev, u32 domain) +{ + const u32 pwr_cmd = PWR_COMMAND_DEF(PWR_COMMAND_DELEGATE, domain, 0); + const u64 pwr_status = gpu_read64(ptdev, PWR_STATUS); + const u64 allow_mask = PWR_STATUS_DOMAIN_ALLOWED(domain); + const u64 delegated_mask = PWR_STATUS_DOMAIN_DELEGATED(domain); + u64 val; + int ret; + + if (drm_WARN_ON(&ptdev->base, domain == PWR_COMMAND_DOMAIN_L2)) + return -EPERM; + + /* Already delegated, exit early */ + if (pwr_status & delegated_mask) + return 0; + + /* Check if the command is allowed before delegating. */ + if (!(pwr_status & allow_mask)) { + drm_warn(&ptdev->base, "Delegating %s domain not allowed", get_domain_name(domain)); + return -EPERM; + } + + ret = panthor_pwr_domain_wait_transition(ptdev, domain, PWR_TRANSITION_TIMEOUT_US); + if (ret) + return ret; + + panthor_pwr_write_command(ptdev, pwr_cmd, 0); + + /* + * On successful delegation + * allow-flag will be cleared with delegated-flag being set. + */ + ret = gpu_read64_poll_timeout(ptdev, PWR_STATUS, val, + ((delegated_mask | allow_mask) & val) == delegated_mask, + 10, PWR_TRANSITION_TIMEOUT_US); + if (ret) { + drm_err(&ptdev->base, "Delegating %s domain timeout, cmd(0x%x)", + get_domain_name(domain), pwr_cmd); + return ret; + } + + return 0; +} + +static int panthor_pwr_delegate_domains(struct panthor_device *ptdev) +{ + int ret; + + if (!ptdev->pwr) + return 0; + + ret = delegate_domain(ptdev, PWR_COMMAND_DOMAIN_SHADER); + if (ret) + return ret; + + ret = delegate_domain(ptdev, PWR_COMMAND_DOMAIN_TILER); + if (ret) + goto err_retract_shader; + + return 0; + +err_retract_shader: + retract_domain(ptdev, PWR_COMMAND_DOMAIN_SHADER); + + return ret; +} + +/** + * panthor_pwr_domain_force_off - Forcefully power down a domain. + * @ptdev: Device. + * @domain: Domain to forcefully power down. + * + * This function will attempt to retract and power off the requested power + * domain. However, if retraction fails, the operation is aborted. If power off + * fails, the domain will remain retracted and under the host control. + * + * Return: 0 on success or a negative error code on failure. + */ +static int panthor_pwr_domain_force_off(struct panthor_device *ptdev, u32 domain) +{ + const u64 domain_ready = gpu_read64(ptdev, get_domain_ready_reg(domain)); + int ret; + + /* Domain already powered down, early exit. */ + if (!domain_ready) + return 0; + + /* Domain has to be in host control to issue power off command. */ + ret = retract_domain(ptdev, domain); + if (ret) + return ret; + + return panthor_pwr_domain_power_off(ptdev, domain, domain_ready, PWR_TRANSITION_TIMEOUT_US); +} + void panthor_pwr_unplug(struct panthor_device *ptdev) { unsigned long flags; @@ -104,6 +429,59 @@ int panthor_pwr_init(struct panthor_device *ptdev) return 0; } +void panthor_pwr_l2_power_off(struct panthor_device *ptdev) +{ + const u64 l2_allow_mask = PWR_STATUS_DOMAIN_ALLOWED(PWR_COMMAND_DOMAIN_L2); + const u64 pwr_status = gpu_read64(ptdev, PWR_STATUS); + + /* Abort if L2 power off constraints are not satisfied */ + if (!(pwr_status & l2_allow_mask)) { + drm_warn(&ptdev->base, "Power off L2 domain not allowed"); + return; + } + + /* It is expected that when halting the MCU, it would power down its + * delegated domains. However, an unresponsive or hung MCU may not do + * so, which is why we need to check and retract the domains back into + * host control to be powered down in the right order before powering + * down the L2. + */ + if (panthor_pwr_domain_force_off(ptdev, PWR_COMMAND_DOMAIN_TILER)) + return; + + if (panthor_pwr_domain_force_off(ptdev, PWR_COMMAND_DOMAIN_SHADER)) + return; + + panthor_pwr_domain_power_off(ptdev, PWR_COMMAND_DOMAIN_L2, ptdev->gpu_info.l2_present, + PWR_TRANSITION_TIMEOUT_US); +} + +int panthor_pwr_l2_power_on(struct panthor_device *ptdev) +{ + const u32 pwr_status = gpu_read64(ptdev, PWR_STATUS); + const u32 l2_allow_mask = PWR_STATUS_DOMAIN_ALLOWED(PWR_COMMAND_DOMAIN_L2); + int ret; + + if ((pwr_status & l2_allow_mask) == 0) { + drm_warn(&ptdev->base, "Power on L2 domain not allowed"); + return -EPERM; + } + + ret = panthor_pwr_domain_power_on(ptdev, PWR_COMMAND_DOMAIN_L2, ptdev->gpu_info.l2_present, + PWR_TRANSITION_TIMEOUT_US); + if (ret) + return ret; + + /* Delegate control of the shader and tiler power domains to the MCU as + * it can better manage which shader/tiler cores need to be powered up + * or can be powered down based on currently running jobs. + * + * If the shader and tiler domains are already delegated to the MCU, + * this call would just return early. + */ + return panthor_pwr_delegate_domains(ptdev); +} + void panthor_pwr_suspend(struct panthor_device *ptdev) { if (!ptdev->pwr) diff --git a/drivers/gpu/drm/panthor/panthor_pwr.h b/drivers/gpu/drm/panthor/panthor_pwr.h index b325e5b7eba3..3c834059a860 100644 --- a/drivers/gpu/drm/panthor/panthor_pwr.h +++ b/drivers/gpu/drm/panthor/panthor_pwr.h @@ -10,6 +10,10 @@ void panthor_pwr_unplug(struct panthor_device *ptdev); int panthor_pwr_init(struct panthor_device *ptdev); +void panthor_pwr_l2_power_off(struct panthor_device *ptdev); + +int panthor_pwr_l2_power_on(struct panthor_device *ptdev); + void panthor_pwr_suspend(struct panthor_device *ptdev); void panthor_pwr_resume(struct panthor_device *ptdev); diff --git a/drivers/gpu/drm/panthor/panthor_regs.h b/drivers/gpu/drm/panthor/panthor_regs.h index 5469eec02178..18702d7001e2 100644 --- a/drivers/gpu/drm/panthor/panthor_regs.h +++ b/drivers/gpu/drm/panthor/panthor_regs.h @@ -72,6 +72,7 @@ #define GPU_FEATURES 0x60 #define GPU_FEATURES_RAY_INTERSECTION BIT(2) +#define GPU_FEATURES_RAY_TRAVERSAL BIT(5) #define GPU_TIMESTAMP_OFFSET 0x88 #define GPU_CYCLE_COUNT 0x90 -- 2.49.0
