From b1d681d8d32499bcf284462d92aeb5f9fe72bf5b Mon Sep 17 00:00:00 2001 From: Georgi Djakov Date: Tue, 25 Aug 2020 20:01:51 +0300 Subject: interconnect: Add sync state support The bootloaders often do some initial configuration of the interconnects in the system and we want to keep this configuration until all consumers have probed and expressed their bandwidth needs. This is because we don't want to change the configuration by starting to disable unused paths until every user had a chance to request the amount of bandwidth it needs. To accomplish this we will implement an interconnect specific sync_state callback which will synchronize (aggregate and set) the current bandwidth settings when all consumers have been probed. Link: https://lore.kernel.org/r/20200825170152.6434-3-georgi.djakov@linaro.org Reviewed-by: Saravana Kannan Signed-off-by: Georgi Djakov --- drivers/interconnect/core.c | 67 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 67 insertions(+) (limited to 'drivers/interconnect') diff --git a/drivers/interconnect/core.c b/drivers/interconnect/core.c index cf07491b7415..b94c6c2b8ff9 100644 --- a/drivers/interconnect/core.c +++ b/drivers/interconnect/core.c @@ -26,6 +26,8 @@ static DEFINE_IDR(icc_idr); static LIST_HEAD(icc_providers); +static int providers_count; +static bool synced_state; static DEFINE_MUTEX(icc_lock); static struct dentry *icc_debugfs_dir; @@ -267,6 +269,12 @@ static int aggregate_requests(struct icc_node *node) } p->aggregate(node, r->tag, avg_bw, peak_bw, &node->avg_bw, &node->peak_bw); + + /* during boot use the initial bandwidth as a floor value */ + if (!synced_state) { + node->avg_bw = max(node->avg_bw, node->init_avg); + node->peak_bw = max(node->peak_bw, node->init_peak); + } } return 0; @@ -931,6 +939,19 @@ void icc_node_add(struct icc_node *node, struct icc_provider *provider) node->provider = provider; list_add_tail(&node->node_list, &provider->nodes); + /* get the initial bandwidth values and sync them with hardware */ + if (provider->get_bw) { + provider->get_bw(node, &node->init_avg, &node->init_peak); + } else { + node->init_avg = INT_MAX; + node->init_peak = INT_MAX; + } + node->avg_bw = node->init_avg; + node->peak_bw = node->init_peak; + provider->set(node, node); + node->avg_bw = 0; + node->peak_bw = 0; + mutex_unlock(&icc_lock); } EXPORT_SYMBOL_GPL(icc_node_add); @@ -1026,8 +1047,54 @@ int icc_provider_del(struct icc_provider *provider) } EXPORT_SYMBOL_GPL(icc_provider_del); +static int of_count_icc_providers(struct device_node *np) +{ + struct device_node *child; + int count = 0; + + for_each_available_child_of_node(np, child) { + if (of_property_read_bool(child, "#interconnect-cells")) + count++; + count += of_count_icc_providers(child); + } + of_node_put(np); + + return count; +} + +void icc_sync_state(struct device *dev) +{ + struct icc_provider *p; + struct icc_node *n; + static int count; + + count++; + + if (count < providers_count) + return; + + mutex_lock(&icc_lock); + synced_state = true; + list_for_each_entry(p, &icc_providers, provider_list) { + dev_dbg(p->dev, "interconnect provider is in synced state\n"); + list_for_each_entry(n, &p->nodes, node_list) { + if (n->init_avg || n->init_peak) { + aggregate_requests(n); + p->set(n, n); + } + } + } + mutex_unlock(&icc_lock); +} +EXPORT_SYMBOL_GPL(icc_sync_state); + static int __init icc_init(void) { + struct device_node *root = of_find_node_by_path("/"); + + providers_count = of_count_icc_providers(root); + of_node_put(root); + icc_debugfs_dir = debugfs_create_dir("interconnect", NULL); debugfs_create_file("interconnect_summary", 0444, icc_debugfs_dir, NULL, &icc_summary_fops); -- cgit v1.2.3 From 7d3b0b0d8184ce4a20fd9f48cd12484139bec939 Mon Sep 17 00:00:00 2001 From: Georgi Djakov Date: Tue, 25 Aug 2020 20:01:52 +0300 Subject: interconnect: qcom: Use icc_sync_state Lowering the bandwidth on the bus might have negative consequences if it's done before all consumers had a chance to cast their vote. Now by default the framework sets the bandwidth to maximum during boot. We need to use the icc_sync_state callback to notify the framework when all consumers are probed and there is no need to keep the bandwidth set to maximum anymore. Link: https://lore.kernel.org/r/20200825170152.6434-4-georgi.djakov@linaro.org Reviewed-by: Saravana Kannan Signed-off-by: Georgi Djakov --- drivers/interconnect/qcom/osm-l3.c | 1 + drivers/interconnect/qcom/sc7180.c | 1 + drivers/interconnect/qcom/sdm845.c | 1 + 3 files changed, 3 insertions(+) (limited to 'drivers/interconnect') diff --git a/drivers/interconnect/qcom/osm-l3.c b/drivers/interconnect/qcom/osm-l3.c index 96fb9ff5ff2e..ae955f164442 100644 --- a/drivers/interconnect/qcom/osm-l3.c +++ b/drivers/interconnect/qcom/osm-l3.c @@ -268,6 +268,7 @@ static struct platform_driver osm_l3_driver = { .driver = { .name = "osm-l3", .of_match_table = osm_l3_of_match, + .sync_state = icc_sync_state, }, }; module_platform_driver(osm_l3_driver); diff --git a/drivers/interconnect/qcom/sc7180.c b/drivers/interconnect/qcom/sc7180.c index dcf493d07928..4c5d38649220 100644 --- a/drivers/interconnect/qcom/sc7180.c +++ b/drivers/interconnect/qcom/sc7180.c @@ -633,6 +633,7 @@ static struct platform_driver qnoc_driver = { .driver = { .name = "qnoc-sc7180", .of_match_table = qnoc_of_match, + .sync_state = icc_sync_state, }, }; module_platform_driver(qnoc_driver); diff --git a/drivers/interconnect/qcom/sdm845.c b/drivers/interconnect/qcom/sdm845.c index f6c7b969520d..6aa39aad2555 100644 --- a/drivers/interconnect/qcom/sdm845.c +++ b/drivers/interconnect/qcom/sdm845.c @@ -559,6 +559,7 @@ static struct platform_driver qnoc_driver = { .driver = { .name = "qnoc-sdm845", .of_match_table = qnoc_of_match, + .sync_state = icc_sync_state, }, }; module_platform_driver(qnoc_driver); -- cgit v1.2.3