From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4312A279DC9; Mon, 13 Oct 2025 15:33:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760369631; cv=none; b=XICFP1N692gZ9Eqibi5ehz4jU0Rfv2g1vULm/YRh92iN1I8HCJEeSDdSRXz3NDISZvJ243ft+QnmWyszUcjgnYveERrAfYKMa6l+BF+Z2IFV562qz4QUwswAz7OxhcmaEm16ssYhlaC7i8DTzdLhXYWYE4mmNGhZsxVhd+8IP1Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760369631; c=relaxed/simple; bh=bGE3GGZaPgveyj7IYW+iVsrp4w5FL8wm+F3biMWsZLY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=QK0ejca66gjgzOPkB+hx1mIQgyUQJLo6qt8W4MZan68F3GfSu2LHSW5Hc3yex4BFun+hgtBDfsiId+mj6S3R0P09KDzI/+CZ79Ze8adEL3Mj6JE4YhL/CNcNJzQ+eeRQeBPU6MG82SwJEsVd6dzGvSY9PlHx5MqnP80ol1CRfAU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=v7fx4Qf+; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="v7fx4Qf+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BCF75C4CEE7; Mon, 13 Oct 2025 15:33:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1760369631; bh=bGE3GGZaPgveyj7IYW+iVsrp4w5FL8wm+F3biMWsZLY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=v7fx4Qf+I2DfhCBHBRWmOfEeTDBrRZRfLVCbPu8n55HiPaqk4RiKm/1PvXZ4aG5FZ hH6PrOhQln39NhTSrYZvSJ2Xhk8fuBzp3KDYXBihBak7q84DtUbLFwLe8QXCSw9OCI VC7v2enempLAhu3RO5+iKady8UvB2R6TjsVmcK5Q= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Qiang Yu , Ziyue Zhang , Manivannan Sadhasivam , Sasha Levin Subject: [PATCH 6.17 315/563] PCI: qcom: Add equalization settings for 8.0 GT/s and 32.0 GT/s Date: Mon, 13 Oct 2025 16:42:56 +0200 Message-ID: <20251013144422.676821006@linuxfoundation.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251013144411.274874080@linuxfoundation.org> References: <20251013144411.274874080@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ziyue Zhang [ Upstream commit 37bf0f4e39de9b53bc6f8d3702b021e2c6b5bae3 ] Add lane equalization setting for 8.0 GT/s and 32.0 GT/s to enhance link stability and avoid AER Correctable Errors reported on some platforms (eg. SA8775P). 8.0 GT/s, 16.0 GT/s and 32.0 GT/s require the same equalization setting. This setting is programmed into a group of shadow registers, which can be switched to configure equalization for different speeds by writing 00b, 01b and 10b to `RATE_SHADOW_SEL`. Hence, program equalization registers in a loop using link speed as index, so that equalization setting can be programmed for 8.0 GT/s, 16.0 GT/s and 32.0 GT/s. Fixes: 489f14be0e0a ("arm64: dts: qcom: sa8775p: Add pcie0 and pcie1 nodes") Co-developed-by: Qiang Yu Signed-off-by: Qiang Yu Signed-off-by: Ziyue Zhang [mani: wrapped the warning to fit 100 columns, used post-increment for loop] Signed-off-by: Manivannan Sadhasivam Link: https://patch.msgid.link/20250904065225.1762793-2-ziyue.zhang@oss.qualcomm.com Signed-off-by: Sasha Levin --- drivers/pci/controller/dwc/pcie-designware.h | 1 - drivers/pci/controller/dwc/pcie-qcom-common.c | 58 +++++++++++-------- drivers/pci/controller/dwc/pcie-qcom-common.h | 2 +- drivers/pci/controller/dwc/pcie-qcom-ep.c | 6 +- drivers/pci/controller/dwc/pcie-qcom.c | 6 +- 5 files changed, 41 insertions(+), 32 deletions(-) diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h index 00f52d472dcdd..cc71a2d90cd48 100644 --- a/drivers/pci/controller/dwc/pcie-designware.h +++ b/drivers/pci/controller/dwc/pcie-designware.h @@ -123,7 +123,6 @@ #define GEN3_RELATED_OFF_GEN3_EQ_DISABLE BIT(16) #define GEN3_RELATED_OFF_RATE_SHADOW_SEL_SHIFT 24 #define GEN3_RELATED_OFF_RATE_SHADOW_SEL_MASK GENMASK(25, 24) -#define GEN3_RELATED_OFF_RATE_SHADOW_SEL_16_0GT 0x1 #define GEN3_EQ_CONTROL_OFF 0x8A8 #define GEN3_EQ_CONTROL_OFF_FB_MODE GENMASK(3, 0) diff --git a/drivers/pci/controller/dwc/pcie-qcom-common.c b/drivers/pci/controller/dwc/pcie-qcom-common.c index 3aad19b56da8f..0c6f4514f922f 100644 --- a/drivers/pci/controller/dwc/pcie-qcom-common.c +++ b/drivers/pci/controller/dwc/pcie-qcom-common.c @@ -8,9 +8,11 @@ #include "pcie-designware.h" #include "pcie-qcom-common.h" -void qcom_pcie_common_set_16gt_equalization(struct dw_pcie *pci) +void qcom_pcie_common_set_equalization(struct dw_pcie *pci) { + struct device *dev = pci->dev; u32 reg; + u16 speed; /* * GEN3_RELATED_OFF register is repurposed to apply equalization @@ -19,32 +21,40 @@ void qcom_pcie_common_set_16gt_equalization(struct dw_pcie *pci) * determines the data rate for which these equalization settings are * applied. */ - reg = dw_pcie_readl_dbi(pci, GEN3_RELATED_OFF); - reg &= ~GEN3_RELATED_OFF_GEN3_ZRXDC_NONCOMPL; - reg &= ~GEN3_RELATED_OFF_RATE_SHADOW_SEL_MASK; - reg |= FIELD_PREP(GEN3_RELATED_OFF_RATE_SHADOW_SEL_MASK, - GEN3_RELATED_OFF_RATE_SHADOW_SEL_16_0GT); - dw_pcie_writel_dbi(pci, GEN3_RELATED_OFF, reg); - reg = dw_pcie_readl_dbi(pci, GEN3_EQ_FB_MODE_DIR_CHANGE_OFF); - reg &= ~(GEN3_EQ_FMDC_T_MIN_PHASE23 | - GEN3_EQ_FMDC_N_EVALS | - GEN3_EQ_FMDC_MAX_PRE_CUSROR_DELTA | - GEN3_EQ_FMDC_MAX_POST_CUSROR_DELTA); - reg |= FIELD_PREP(GEN3_EQ_FMDC_T_MIN_PHASE23, 0x1) | - FIELD_PREP(GEN3_EQ_FMDC_N_EVALS, 0xd) | - FIELD_PREP(GEN3_EQ_FMDC_MAX_PRE_CUSROR_DELTA, 0x5) | - FIELD_PREP(GEN3_EQ_FMDC_MAX_POST_CUSROR_DELTA, 0x5); - dw_pcie_writel_dbi(pci, GEN3_EQ_FB_MODE_DIR_CHANGE_OFF, reg); + for (speed = PCIE_SPEED_8_0GT; speed <= pcie_link_speed[pci->max_link_speed]; speed++) { + if (speed > PCIE_SPEED_32_0GT) { + dev_warn(dev, "Skipped equalization settings for unsupported data rate\n"); + break; + } - reg = dw_pcie_readl_dbi(pci, GEN3_EQ_CONTROL_OFF); - reg &= ~(GEN3_EQ_CONTROL_OFF_FB_MODE | - GEN3_EQ_CONTROL_OFF_PHASE23_EXIT_MODE | - GEN3_EQ_CONTROL_OFF_FOM_INC_INITIAL_EVAL | - GEN3_EQ_CONTROL_OFF_PSET_REQ_VEC); - dw_pcie_writel_dbi(pci, GEN3_EQ_CONTROL_OFF, reg); + reg = dw_pcie_readl_dbi(pci, GEN3_RELATED_OFF); + reg &= ~GEN3_RELATED_OFF_GEN3_ZRXDC_NONCOMPL; + reg &= ~GEN3_RELATED_OFF_RATE_SHADOW_SEL_MASK; + reg |= FIELD_PREP(GEN3_RELATED_OFF_RATE_SHADOW_SEL_MASK, + speed - PCIE_SPEED_8_0GT); + dw_pcie_writel_dbi(pci, GEN3_RELATED_OFF, reg); + + reg = dw_pcie_readl_dbi(pci, GEN3_EQ_FB_MODE_DIR_CHANGE_OFF); + reg &= ~(GEN3_EQ_FMDC_T_MIN_PHASE23 | + GEN3_EQ_FMDC_N_EVALS | + GEN3_EQ_FMDC_MAX_PRE_CUSROR_DELTA | + GEN3_EQ_FMDC_MAX_POST_CUSROR_DELTA); + reg |= FIELD_PREP(GEN3_EQ_FMDC_T_MIN_PHASE23, 0x1) | + FIELD_PREP(GEN3_EQ_FMDC_N_EVALS, 0xd) | + FIELD_PREP(GEN3_EQ_FMDC_MAX_PRE_CUSROR_DELTA, 0x5) | + FIELD_PREP(GEN3_EQ_FMDC_MAX_POST_CUSROR_DELTA, 0x5); + dw_pcie_writel_dbi(pci, GEN3_EQ_FB_MODE_DIR_CHANGE_OFF, reg); + + reg = dw_pcie_readl_dbi(pci, GEN3_EQ_CONTROL_OFF); + reg &= ~(GEN3_EQ_CONTROL_OFF_FB_MODE | + GEN3_EQ_CONTROL_OFF_PHASE23_EXIT_MODE | + GEN3_EQ_CONTROL_OFF_FOM_INC_INITIAL_EVAL | + GEN3_EQ_CONTROL_OFF_PSET_REQ_VEC); + dw_pcie_writel_dbi(pci, GEN3_EQ_CONTROL_OFF, reg); + } } -EXPORT_SYMBOL_GPL(qcom_pcie_common_set_16gt_equalization); +EXPORT_SYMBOL_GPL(qcom_pcie_common_set_equalization); void qcom_pcie_common_set_16gt_lane_margining(struct dw_pcie *pci) { diff --git a/drivers/pci/controller/dwc/pcie-qcom-common.h b/drivers/pci/controller/dwc/pcie-qcom-common.h index 7d88d29e47661..7f5ca2fd9a72f 100644 --- a/drivers/pci/controller/dwc/pcie-qcom-common.h +++ b/drivers/pci/controller/dwc/pcie-qcom-common.h @@ -8,7 +8,7 @@ struct dw_pcie; -void qcom_pcie_common_set_16gt_equalization(struct dw_pcie *pci); +void qcom_pcie_common_set_equalization(struct dw_pcie *pci); void qcom_pcie_common_set_16gt_lane_margining(struct dw_pcie *pci); #endif diff --git a/drivers/pci/controller/dwc/pcie-qcom-ep.c b/drivers/pci/controller/dwc/pcie-qcom-ep.c index bf7c6ac0f3e39..aaf060bf39d40 100644 --- a/drivers/pci/controller/dwc/pcie-qcom-ep.c +++ b/drivers/pci/controller/dwc/pcie-qcom-ep.c @@ -511,10 +511,10 @@ static int qcom_pcie_perst_deassert(struct dw_pcie *pci) goto err_disable_resources; } - if (pcie_link_speed[pci->max_link_speed] == PCIE_SPEED_16_0GT) { - qcom_pcie_common_set_16gt_equalization(pci); + qcom_pcie_common_set_equalization(pci); + + if (pcie_link_speed[pci->max_link_speed] == PCIE_SPEED_16_0GT) qcom_pcie_common_set_16gt_lane_margining(pci); - } /* * The physical address of the MMIO region which is exposed as the BAR diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c index fbed7130d7475..a93740ae602f2 100644 --- a/drivers/pci/controller/dwc/pcie-qcom.c +++ b/drivers/pci/controller/dwc/pcie-qcom.c @@ -322,10 +322,10 @@ static int qcom_pcie_start_link(struct dw_pcie *pci) { struct qcom_pcie *pcie = to_qcom_pcie(pci); - if (pcie_link_speed[pci->max_link_speed] == PCIE_SPEED_16_0GT) { - qcom_pcie_common_set_16gt_equalization(pci); + qcom_pcie_common_set_equalization(pci); + + if (pcie_link_speed[pci->max_link_speed] == PCIE_SPEED_16_0GT) qcom_pcie_common_set_16gt_lane_margining(pci); - } /* Enable Link Training state machine */ if (pcie->cfg->ops->ltssm_enable) -- 2.51.0