Re: [Patch v1 01/10] memory: tegra: add interconnect support for DRAM scaling in Tegra234

From: Sumit Gupta
Date: Fri Jan 13 2023 - 07:46:27 EST




On 22/12/22 21:26, Dmitry Osipenko wrote:
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21.12.2022 22:20, Dmitry Osipenko пишет:
20.12.2022 19:02, Sumit Gupta пишет:
+static int tegra_emc_icc_set_bw(struct icc_node *src, struct icc_node *dst)
+{
+ struct tegra186_emc *emc = to_tegra186_emc(dst->provider);
+ struct tegra_mc *mc = dev_get_drvdata(emc->dev->parent);
+ struct mrq_bwmgr_int_request bwmgr_req = { 0 };
+ struct mrq_bwmgr_int_response bwmgr_resp = { 0 };
+ struct tegra_icc_node *tnode = mc->curr_tnode;
+ struct tegra_bpmp_message msg;
+ int ret = 0;
+
+ /*
+ * Same Src and Dst node will happen during boot from icc_node_add().
+ * This can be used to pre-initialize and set bandwidth for all clients
+ * before their drivers are loaded. We are skipping this case as for us,
+ * the pre-initialization already happened in Bootloader(MB2) and BPMP-FW.
+ */
+ if (src->id == dst->id)
+ return 0;
+
+ if (mc->curr_tnode->type == TEGRA_ICC_NISO)

The mc->curr_tnode usage looks suspicious, why you can't use src node?


This function sets memory BW for a memory client and not for EMC.
Apparently, you should move the BW setting to tegra234_mc_icc_set() and
then tegra_emc_icc_set_bw() will be a noop.

Yes, will move this code to set_bw() in MC driver. The set_bw call in EMC will be a dummy function after change.
This change will also help to remove "struct tegra_icc_node *curr_tnode;" from "struct tegra_mc" which is used for passing data between MC and EMC drivers to transfer to BPMP.

static int tegra_emc_icc_set_bw(struct icc_node *src, struct icc_node *dst)
{
return 0;
}