From 0f22edd351319b142491c3bbde0be993fb252b30 Mon Sep 17 00:00:00 2001 From: Phil Elwell Date: Wed, 1 Nov 2023 10:13:29 +0000 Subject: [PATCH] PCI: brcmstb: Change RCB_{MPS,64B}_MODE bits Upstream commit [1] unconditionally sets the RCB_MPS and RCB_64B bits that govern where packets are split. We think this is potentially harmful, particularly on CM4 and Pi 5 where potentially any PCIe devices could be attached. Make RCB_MPS conditional on a DT property and never set RCB_64B. [1] commit 602fb860945f ("PCI: brcmstb: Set RCB_{MPS,64B}_MODE bits") Signed-off-by: Phil Elwell --- drivers/pci/controller/pcie-brcmstb.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c index 3a80b65..3722443 100644 --- a/drivers/pci/controller/pcie-brcmstb.c +++ b/drivers/pci/controller/pcie-brcmstb.c @@ -336,6 +336,7 @@ struct brcm_pcie { struct device_node *np; bool ssc; bool l1ss; + bool rcb_mps_mode; int gen; u64 msi_target_addr; struct brcm_msi *msi; @@ -1196,14 +1197,14 @@ static int brcm_pcie_setup(struct brcm_pcie *pcie) /* * Set SCB_MAX_BURST_SIZE, CFG_READ_UR_MODE, SCB_ACCESS_EN, - * RCB_MPS_MODE, RCB_64B_MODE + * RCB_MPS_MODE */ tmp = readl(base + PCIE_MISC_MISC_CTRL); u32p_replace_bits(&tmp, 1, PCIE_MISC_MISC_CTRL_SCB_ACCESS_EN_MASK); u32p_replace_bits(&tmp, 1, PCIE_MISC_MISC_CTRL_CFG_READ_UR_MODE_MASK); u32p_replace_bits(&tmp, burst, PCIE_MISC_MISC_CTRL_MAX_BURST_SIZE_MASK); - u32p_replace_bits(&tmp, 1, PCIE_MISC_MISC_CTRL_PCIE_RCB_MPS_MODE_MASK); - u32p_replace_bits(&tmp, 1, PCIE_MISC_MISC_CTRL_PCIE_RCB_64B_MODE_MASK); + if (pcie->rcb_mps_mode) + u32p_replace_bits(&tmp, 1, PCIE_MISC_MISC_CTRL_PCIE_RCB_MPS_MODE_MASK); writel(tmp, base + PCIE_MISC_MISC_CTRL); brcm_pcie_set_tc_qos(pcie); @@ -1917,6 +1918,7 @@ static int brcm_pcie_probe(struct platform_device *pdev) pcie->ssc = of_property_read_bool(np, "brcm,enable-ssc"); pcie->l1ss = of_property_read_bool(np, "brcm,enable-l1ss"); + pcie->rcb_mps_mode = of_property_read_bool(np, "brcm,enable-mps-rcb"); ret = clk_prepare_enable(pcie->clk); if (ret) { -- 2.7.4