The series add supports for SiFive DDR controller driver. This driver
is use to manage the Cadence DDR controller present in SiFive SoCs.
Currently it manages only the EDAC feature of the DDR controller.
The series also adds Memory controller EDAC support for SiFive platform.
It register for notifier event from SiFive DDR controller driver.
The series is tested and based on Linux v5.8.
For testing on Hifive Unleashed:
1. Enable the ECC bit of DDR controller during DDR initialization
2. Erase the entire DRAM in bootloader stage
3. Using FWC feature of DDR controller force ecc error to test
Changes in v2:
Incorporate below changes in EDAC patch as suggested by Borislav Petkov
- Replace all ifdeffery with if(IS_ENABLED(CONFIG_...))
- A few textual changes in patch description and code
Yash Shah (3):
dt-bindings: riscv: Add DT documentation for DDR Controller in SiFive
SoCs
soc: sifive: Add SiFive specific Cadence DDR controller driver
EDAC/sifive: Add EDAC support for Memory Controller in SiFive SoCs
.../devicetree/bindings/riscv/sifive-ddr.yaml | 41 ++++
drivers/edac/Kconfig | 2 +-
drivers/edac/sifive_edac.c | 119 +++++++++++-
drivers/soc/sifive/Kconfig | 6 +
drivers/soc/sifive/Makefile | 3 +-
drivers/soc/sifive/sifive_ddr.c | 207 +++++++++++++++++++++
include/soc/sifive/sifive_ddr.h | 73 ++++++++
7 files changed, 447 insertions(+), 4 deletions(-)
create mode 100644 Documentation/devicetree/bindings/riscv/sifive-ddr.yaml
create mode 100644 drivers/soc/sifive/sifive_ddr.c
create mode 100644 include/soc/sifive/sifive_ddr.h
--
2.7.4
Add a driver to manage the Cadence DDR controller present on SiFive SoCs
At present the driver manages the EDAC feature of the DDR controller.
Additional features may be added to the driver in future to control
other aspects of the DDR controller.
Signed-off-by: Yash Shah <[email protected]>
Reviewed-by: Palmer Dabbelt <[email protected]>
Acked-by: Palmer Dabbelt <[email protected]>
---
drivers/soc/sifive/Kconfig | 6 ++
drivers/soc/sifive/Makefile | 3 +-
drivers/soc/sifive/sifive_ddr.c | 207 ++++++++++++++++++++++++++++++++++++++++
include/soc/sifive/sifive_ddr.h | 73 ++++++++++++++
4 files changed, 288 insertions(+), 1 deletion(-)
create mode 100644 drivers/soc/sifive/sifive_ddr.c
create mode 100644 include/soc/sifive/sifive_ddr.h
diff --git a/drivers/soc/sifive/Kconfig b/drivers/soc/sifive/Kconfig
index 58cf8c4..f41d8fe 100644
--- a/drivers/soc/sifive/Kconfig
+++ b/drivers/soc/sifive/Kconfig
@@ -7,4 +7,10 @@ config SIFIVE_L2
help
Support for the L2 cache controller on SiFive platforms.
+config SIFIVE_DDR
+ bool "Sifive DDR controller driver"
+ help
+ Support for the management of cadence DDR controller on SiFive
+ platforms.
+
endif
diff --git a/drivers/soc/sifive/Makefile b/drivers/soc/sifive/Makefile
index b5caff7..b4acb5c 100644
--- a/drivers/soc/sifive/Makefile
+++ b/drivers/soc/sifive/Makefile
@@ -1,3 +1,4 @@
# SPDX-License-Identifier: GPL-2.0
-obj-$(CONFIG_SIFIVE_L2) += sifive_l2_cache.o
+obj-$(CONFIG_SIFIVE_L2) += sifive_l2_cache.o
+obj-$(CONFIG_SIFIVE_DDR) += sifive_ddr.o
diff --git a/drivers/soc/sifive/sifive_ddr.c b/drivers/soc/sifive/sifive_ddr.c
new file mode 100644
index 0000000..b1b421c
--- /dev/null
+++ b/drivers/soc/sifive/sifive_ddr.c
@@ -0,0 +1,207 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SiFive specific cadence DDR controller Driver
+ *
+ * Copyright (C) 2019-2020 SiFive, Inc.
+ *
+ */
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/module.h>
+#include <linux/uaccess.h>
+#include <linux/delay.h>
+#include <soc/sifive/sifive_ddr.h>
+
+static ATOMIC_NOTIFIER_HEAD(ddr_err_chain);
+
+int register_sifive_ddr_error_notifier(struct notifier_block *nb)
+{
+ return atomic_notifier_chain_register(&ddr_err_chain, nb);
+}
+EXPORT_SYMBOL_GPL(register_sifive_ddr_error_notifier);
+
+int unregister_sifive_ddr_error_notifier(struct notifier_block *nb)
+{
+ return atomic_notifier_chain_unregister(&ddr_err_chain, nb);
+}
+EXPORT_SYMBOL_GPL(unregister_sifive_ddr_error_notifier);
+
+static void handle_ce(struct sifive_ddr_priv *pv)
+{
+ u64 err_c_addr = 0x0;
+ u64 err_c_data = 0x0;
+ u32 err_c_synd, err_c_id;
+ u32 sig_val_l, sig_val_h;
+
+ sig_val_l = readl(pv->reg + ECC_C_ADDR_L_REG);
+ sig_val_h = (readl(pv->reg + ECC_C_ADDR_H_REG) &
+ ECC_ADDR_H_MASK);
+ err_c_addr = (((ulong)sig_val_h << CTL_REG_WIDTH_SHIFT) | sig_val_l);
+
+ sig_val_l = readl(pv->reg + ECC_C_DATA_L_REG);
+ sig_val_h = readl(pv->reg + ECC_C_DATA_H_REG);
+ err_c_data = (((ulong)sig_val_h << CTL_REG_WIDTH_SHIFT) | sig_val_l);
+
+ err_c_id = ((readl(pv->reg + ECC_U_C_ID_REG) &
+ ECC_C_ID_MASK) >> ECC_C_ID_SHIFT);
+
+ err_c_synd = ((readl(pv->reg + ECC_C_SYND_REG) &
+ ECC_SYND_MASK) >> ECC_SYND_SHIFT);
+
+ pv->error_count = 1;
+ pv->page_frame_number = err_c_addr >> PAGE_SHIFT;
+ pv->offset_in_page = err_c_addr & ~PAGE_MASK;
+ pv->syndrome = err_c_synd;
+ pv->top_layer = 0;
+ pv->mid_layer = 0;
+ pv->low_layer = -1;
+
+ atomic_notifier_call_chain(&ddr_err_chain, SIFIVE_DDR_ERR_TYPE_CE, pv);
+}
+
+static void handle_ue(struct sifive_ddr_priv *pv)
+{
+ u64 err_u_addr = 0x0;
+ u64 err_u_data = 0x0;
+ u32 err_u_synd, err_u_id;
+ u32 sig_val_l, sig_val_h;
+
+ sig_val_l = readl(pv->reg + ECC_U_ADDR_L_REG);
+ sig_val_h = (readl(pv->reg + ECC_U_ADDR_H_REG) &
+ ECC_ADDR_H_MASK);
+ err_u_addr = (((ulong)sig_val_h << CTL_REG_WIDTH_SHIFT) | sig_val_l);
+
+ sig_val_l = readl(pv->reg + ECC_U_DATA_L_REG);
+ sig_val_h = readl(pv->reg + ECC_U_DATA_H_REG);
+ err_u_data = (((ulong)sig_val_h << CTL_REG_WIDTH_SHIFT) | sig_val_l);
+
+ err_u_id = ((readl(pv->reg + ECC_U_C_ID_REG) &
+ ECC_U_ID_MASK) >> ECC_U_ID_SHIFT);
+
+ err_u_synd = ((readl(pv->reg + ECC_U_SYND_REG) &
+ ECC_SYND_MASK) >> ECC_SYND_SHIFT);
+
+ pv->error_count = 1;
+ pv->page_frame_number = err_u_addr >> PAGE_SHIFT;
+ pv->offset_in_page = err_u_addr & ~PAGE_MASK;
+ pv->syndrome = err_u_synd;
+ pv->top_layer = 0;
+ pv->mid_layer = 0;
+ pv->low_layer = -1;
+
+ atomic_notifier_call_chain(&ddr_err_chain, SIFIVE_DDR_ERR_TYPE_UE, pv);
+}
+
+static irqreturn_t ecc_isr(int irq, void *ptr)
+{
+ struct sifive_ddr_priv *pv = ptr;
+ u32 intr_status;
+ u32 val;
+
+ /* Check the intr status and confirm ECC error intr */
+ intr_status = readl(pv->reg + ECC_CTL_INT_STATUS_REG);
+
+ dev_dbg(pv->dev, "InterruptStatus : 0x%x\n", intr_status);
+ val = intr_status & (ECC_INT_CE_UE_MASK);
+ if (!((val & ECC_CE_INTR_MASK) || (val & ECC_UE_INTR_MASK)))
+ return IRQ_NONE;
+
+ if (val & ECC_CE_INTR_MASK) {
+ handle_ce(pv);
+
+ /* Clear the interrupt source */
+ if (val & ECC_INT_CE_EVENT)
+ writel(ECC_INT_CE_EVENT,
+ pv->reg + ECC_CTL_INT_ACK_REG);
+ else if (val & ECC_INT_SECOND_CE_EVENT)
+ writel(ECC_INT_SECOND_CE_EVENT,
+ pv->reg + ECC_CTL_INT_ACK_REG);
+ else
+ dev_err(pv->dev, "Failed to clear IRQ\n");
+ }
+
+ if (val & ECC_UE_INTR_MASK) {
+ handle_ue(pv);
+
+ /* Clear the interrupt source */
+ if (val & ECC_INT_UE_EVENT)
+ writel(ECC_INT_UE_EVENT,
+ pv->reg + ECC_CTL_INT_ACK_REG);
+ else if (val & ECC_INT_SECOND_UE_EVENT)
+ writel(ECC_INT_SECOND_UE_EVENT,
+ pv->reg + ECC_CTL_INT_ACK_REG);
+ else
+ dev_err(pv->dev, "Failed to clear IRQ\n");
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int sifive_ddr_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct sifive_ddr_priv *priv;
+ struct resource *res;
+ int ret, irq;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->dev = dev;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ priv->reg = devm_ioremap_resource(dev, res);
+ if (IS_ERR(priv->reg))
+ return PTR_ERR(priv->reg);
+
+ irq = platform_get_irq(pdev, 0);
+ ret = devm_request_irq(dev, irq, ecc_isr, 0, "sifive-fu540-ddr", priv);
+ if (ret) {
+ dev_err(dev, "request_irq failed\n");
+ return ret;
+ }
+
+ /* Enable & set CE/UE Interrupts for DDR4 Controller */
+ writel(~(ECC_INT_CE_UE_MASK), priv->reg + ECC_CTL_INT_MASK_REG);
+
+ platform_set_drvdata(pdev, priv);
+ dev_info(dev, "SiFive DDR probe successful\n");
+
+ return 0;
+}
+
+static int sifive_ddr_remove(struct platform_device *pdev)
+{
+ struct sifive_ddr_priv *priv = platform_get_drvdata(pdev);
+
+ /* Disable All ECC Interrupts for DDR4 Controller */
+ writel(ECC_INT_CE_UE_MASK, priv->reg + ECC_CTL_INT_MASK_REG);
+
+ return 0;
+}
+
+static const struct of_device_id sifive_ddr_of_match[] = {
+ { .compatible = "sifive,fu540-c000-ddr"},
+ {},
+};
+
+MODULE_DEVICE_TABLE(of, sifive_ddr_of_match);
+
+static struct platform_driver sifive_ddr_driver = {
+ .driver = {
+ .name = "sifive-ddr",
+ .of_match_table = sifive_ddr_of_match,
+ },
+ .probe = sifive_ddr_probe,
+ .remove = sifive_ddr_remove,
+};
+
+module_platform_driver(sifive_ddr_driver);
+
+MODULE_AUTHOR("SiFive");
+MODULE_DESCRIPTION("SiFive DDR Controller driver");
+MODULE_LICENSE("GPL v2");
diff --git a/include/soc/sifive/sifive_ddr.h b/include/soc/sifive/sifive_ddr.h
new file mode 100644
index 0000000..2ff8623
--- /dev/null
+++ b/include/soc/sifive/sifive_ddr.h
@@ -0,0 +1,73 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * SiFive DDR Controller header file
+ *
+ */
+
+#ifndef __SOC_SIFIVE_DDR_H
+#define __SOC_SIFIVE_DDR_H
+
+int register_sifive_ddr_error_notifier(struct notifier_block *nb);
+int unregister_sifive_ddr_error_notifier(struct notifier_block *nb);
+
+struct sifive_ddr_priv {
+ void __iomem *reg;
+ struct device *dev;
+ u16 error_count;
+ unsigned long page_frame_number;
+ unsigned long offset_in_page;
+ unsigned long syndrome;
+ int top_layer;
+ int mid_layer;
+ int low_layer;
+};
+
+#define SIFIVE_DDR_ERR_TYPE_CE (0)
+#define SIFIVE_DDR_ERR_TYPE_UE (1)
+#define SIFIVE_DDR_EDAC_GRAIN (1)
+#define SIFIVE_MEM_TYPE_DDR4 0xA
+#define SIFIVE_DDR_WIDTH_16 (2)
+#define SIFIVE_DDR_WIDTH_32 (1)
+#define SIFIVE_DDR_WIDTH_64 (0)
+
+#define DDR_CTL_MEM_TYPE_REG 0x000
+#define DDR_CTL_MEM_WIDTH_REG 0x004
+#define ECC_CTL_CONTROL_REG 0x174
+#define ECC_U_ADDR_L_REG 0x180
+#define ECC_U_ADDR_H_REG 0x184
+#define ECC_U_DATA_L_REG 0x188
+#define ECC_U_DATA_H_REG 0x18c
+
+#define ECC_C_ADDR_L_REG 0x190
+#define ECC_C_ADDR_H_REG 0x194
+#define ECC_C_DATA_L_REG 0x198
+#define ECC_C_DATA_H_REG 0x19c
+#define ECC_U_C_ID_REG 0x1A0
+#define ECC_CTL_INT_STATUS_REG 0x210
+#define ECC_CTL_INT_ACK_REG 0x218
+#define ECC_CTL_INT_MASK_REG 0x220
+#define ECC_C_SYND_REG ECC_C_ADDR_H_REG
+#define ECC_U_SYND_REG ECC_U_ADDR_H_REG
+
+#define ECC_CTL_MTYPE_MASK GENMASK(11, 8)
+#define CTL_MEM_MAX_WIDTH_MASK GENMASK(31, 24)
+#define ECC_ADDR_H_MASK GENMASK(3, 0)
+#define ECC_INT_CE_UE_MASK GENMASK(6, 3)
+#define ECC_CE_INTR_MASK GENMASK(4, 3)
+#define ECC_UE_INTR_MASK GENMASK(6, 5)
+#define ECC_INT_CE_EVENT BIT(3)
+#define ECC_INT_SECOND_CE_EVENT BIT(4)
+#define ECC_INT_UE_EVENT BIT(5)
+#define ECC_INT_SECOND_UE_EVENT BIT(6)
+#define ECC_CTL_ECC_ENABLE BIT(16)
+
+#define ECC_C_ID_MASK GENMASK(28, 16)
+#define ECC_U_ID_MASK GENMASK(12, 0)
+#define ECC_C_ID_SHIFT (16)
+#define ECC_U_ID_SHIFT (0)
+#define ECC_SYND_MASK GENMASK(15, 8)
+#define ECC_SYND_SHIFT (8)
+
+#define CTL_REG_WIDTH_SHIFT (32)
+
+#endif /* __SOC_SIFIVE_DDR_H */
--
2.7.4
Add Memory controller EDAC support to the SiFive platform EDAC driver.
It registers for ECC notifier events from the memory controller.
Signed-off-by: Yash Shah <[email protected]>
Reviewed-by: Palmer Dabbelt <[email protected]>
Acked-by: Palmer Dabbelt <[email protected]>
---
drivers/edac/Kconfig | 2 +-
drivers/edac/sifive_edac.c | 119 ++++++++++++++++++++++++++++++++++++++++++++-
2 files changed, 118 insertions(+), 3 deletions(-)
diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig
index 7b6ec30..f8b3b53 100644
--- a/drivers/edac/Kconfig
+++ b/drivers/edac/Kconfig
@@ -462,7 +462,7 @@ config EDAC_ALTERA_SDMMC
config EDAC_SIFIVE
bool "Sifive platform EDAC driver"
- depends on EDAC=y && SIFIVE_L2
+ depends on EDAC=y && (SIFIVE_L2 || SIFIVE_DDR)
help
Support for error detection and correction on the SiFive SoCs.
diff --git a/drivers/edac/sifive_edac.c b/drivers/edac/sifive_edac.c
index 3a3dcb1..17dd556 100644
--- a/drivers/edac/sifive_edac.c
+++ b/drivers/edac/sifive_edac.c
@@ -11,14 +11,119 @@
#include <linux/platform_device.h>
#include "edac_module.h"
#include <soc/sifive/sifive_l2_cache.h>
+#include <soc/sifive/sifive_ddr.h>
#define DRVNAME "sifive_edac"
+#define EDAC_MOD_NAME "Sifive ECC Manager"
struct sifive_edac_priv {
struct notifier_block notifier;
struct edac_device_ctl_info *dci;
};
+struct sifive_edac_mc_priv {
+ struct notifier_block notifier;
+ struct mem_ctl_info *mci;
+};
+
+/**
+ * EDAC MC error callback
+ *
+ * @event: non-zero if unrecoverable.
+ */
+static
+int ecc_mc_err_event(struct notifier_block *this, unsigned long event, void *ptr)
+{
+ struct sifive_ddr_priv *priv = ptr;
+ struct sifive_edac_mc_priv *p;
+
+ p = container_of(this, struct sifive_edac_mc_priv, notifier);
+ if (event == SIFIVE_DDR_ERR_TYPE_UE) {
+ edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, p->mci,
+ priv->error_count, priv->page_frame_number,
+ priv->offset_in_page, priv->syndrome,
+ priv->top_layer, priv->mid_layer,
+ priv->low_layer, p->mci->ctl_name, "");
+ } else if (event == SIFIVE_DDR_ERR_TYPE_CE) {
+ edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, p->mci,
+ priv->error_count, priv->page_frame_number,
+ priv->offset_in_page, priv->syndrome,
+ priv->top_layer, priv->mid_layer,
+ priv->low_layer, p->mci->ctl_name, "");
+ }
+
+ return NOTIFY_OK;
+}
+
+static int ecc_mc_register(struct platform_device *pdev)
+{
+ struct sifive_edac_mc_priv *p;
+ struct edac_mc_layer layers[1];
+ int ret;
+
+ p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL);
+ if (!p)
+ return -ENOMEM;
+
+ p->notifier.notifier_call = ecc_mc_err_event;
+ platform_set_drvdata(pdev, p);
+
+ layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
+ layers[0].size = 1;
+ layers[0].is_virt_csrow = true;
+
+ p->mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers, 0);
+ if (!p->mci) {
+ dev_err(&pdev->dev, "Failed mem allocation for mc instance\n");
+ return -ENOMEM;
+ }
+
+ p->mci->pdev = &pdev->dev;
+ /* Initialize controller capabilities */
+ p->mci->mtype_cap = MEM_FLAG_DDR4;
+ p->mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_SECDED;
+ p->mci->edac_cap = EDAC_FLAG_SECDED;
+ p->mci->scrub_cap = SCRUB_UNKNOWN;
+ p->mci->scrub_mode = SCRUB_HW_PROG;
+ p->mci->ctl_name = dev_name(&pdev->dev);
+ p->mci->dev_name = dev_name(&pdev->dev);
+ p->mci->mod_name = EDAC_MOD_NAME;
+ p->mci->ctl_page_to_phys = NULL;
+
+ /* Interrupt feature is supported by cadence mc */
+ edac_op_state = EDAC_OPSTATE_INT;
+
+ ret = edac_mc_add_mc(p->mci);
+ if (ret) {
+ edac_printk(KERN_ERR, EDAC_MOD_NAME,
+ "Failed to register with EDAC core\n");
+ goto err;
+ }
+
+ if (IS_ENABLED(CONFIG_SIFIVE_DDR))
+ register_sifive_ddr_error_notifier(&p->notifier);
+
+ return 0;
+
+err:
+ edac_mc_free(p->mci);
+
+ return -ENXIO;
+}
+
+static int ecc_mc_unregister(struct platform_device *pdev)
+{
+ struct sifive_edac_mc_priv *p = platform_get_drvdata(pdev);
+
+ if (IS_ENABLED(CONFIG_SIFIVE_DDR))
+ unregister_sifive_ddr_error_notifier(&p->notifier);
+
+ edac_mc_del_mc(&pdev->dev);
+ edac_mc_free(p->mci);
+
+ return 0;
+}
+
/**
* EDAC error callback
*
@@ -67,7 +172,8 @@ static int ecc_register(struct platform_device *pdev)
goto err;
}
- register_sifive_l2_error_notifier(&p->notifier);
+ if (IS_ENABLED(CONFIG_SIFIVE_L2))
+ register_sifive_l2_error_notifier(&p->notifier);
return 0;
@@ -81,7 +187,9 @@ static int ecc_unregister(struct platform_device *pdev)
{
struct sifive_edac_priv *p = platform_get_drvdata(pdev);
- unregister_sifive_l2_error_notifier(&p->notifier);
+ if (IS_ENABLED(CONFIG_SIFIVE_L2))
+ unregister_sifive_l2_error_notifier(&p->notifier);
+
edac_device_del_device(&pdev->dev);
edac_device_free_ctl_info(p->dci);
@@ -102,12 +210,19 @@ static int __init sifive_edac_init(void)
if (ret)
platform_device_unregister(sifive_pdev);
+ ret = ecc_mc_register(sifive_pdev);
+ if (ret) {
+ ecc_unregister(sifive_pdev);
+ platform_device_unregister(sifive_pdev);
+ }
+
return ret;
}
static void __exit sifive_edac_exit(void)
{
ecc_unregister(sifive_pdev);
+ ecc_mc_unregister(sifive_pdev);
platform_device_unregister(sifive_pdev);
}
--
2.7.4
Add device tree bindings for SiFive FU540 DDR controller driver
Signed-off-by: Yash Shah <[email protected]>
Reviewed-by: Palmer Dabbelt <[email protected]>
Acked-by: Palmer Dabbelt <[email protected]>
---
.../devicetree/bindings/riscv/sifive-ddr.yaml | 41 ++++++++++++++++++++++
1 file changed, 41 insertions(+)
create mode 100644 Documentation/devicetree/bindings/riscv/sifive-ddr.yaml
diff --git a/Documentation/devicetree/bindings/riscv/sifive-ddr.yaml b/Documentation/devicetree/bindings/riscv/sifive-ddr.yaml
new file mode 100644
index 0000000..0288119
--- /dev/null
+++ b/Documentation/devicetree/bindings/riscv/sifive-ddr.yaml
@@ -0,0 +1,41 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/riscv/sifive-ddr.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: SiFive DDR memory controller binding
+
+description: |
+ The Sifive DDR controller driver is used to manage the Cadence DDR
+ controller present in SiFive FU540-C000 SoC. Currently the driver is
+ used to manage EDAC feature of the DDR controller.
+
+maintainers:
+ - Yash Shah <[email protected]>
+
+properties:
+ compatible:
+ enum:
+ - sifive,fu540-c000-ddr
+
+ reg:
+ maxItems: 1
+
+ interrupts:
+ maxItems: 1
+
+required:
+ - compatible
+ - reg
+ - interrupts
+
+additionalProperties: false
+
+examples:
+ - |
+ memory-controller@100b0000 {
+ compatible = "sifive,fu540-c000-ddr";
+ reg = <0x100b0000 0x4000>;
+ interrupts = <31>;
+ };
--
2.7.4
On 9/6/20 10:47 PM, Yash Shah wrote:
> diff --git a/drivers/soc/sifive/Kconfig b/drivers/soc/sifive/Kconfig
> index 58cf8c4..f41d8fe 100644
> --- a/drivers/soc/sifive/Kconfig
> +++ b/drivers/soc/sifive/Kconfig
> @@ -7,4 +7,10 @@ config SIFIVE_L2
> help
> Support for the L2 cache controller on SiFive platforms.
>
> +config SIFIVE_DDR
> + bool "Sifive DDR controller driver"
> + help
> + Support for the management of cadence DDR controller on SiFive
Cadence
> + platforms.
> +
> endif
--
~Randy
On Mon, Sep 07, 2020 at 11:17:58AM +0530, Yash Shah wrote:
> Add a driver to manage the Cadence DDR controller present on SiFive SoCs
> At present the driver manages the EDAC feature of the DDR controller.
> Additional features may be added to the driver in future to control
> other aspects of the DDR controller.
So if this is a generic(ish) Cadence IP block shouldn't it be named
Cadence and made generic? Or is the frontend somehow SiFive specific?
On Sun, 06 Sep 2020 23:11:26 PDT (-0700), Christoph Hellwig wrote:
> On Mon, Sep 07, 2020 at 11:17:58AM +0530, Yash Shah wrote:
>> Add a driver to manage the Cadence DDR controller present on SiFive SoCs
>> At present the driver manages the EDAC feature of the DDR controller.
>> Additional features may be added to the driver in future to control
>> other aspects of the DDR controller.
>
> So if this is a generic(ish) Cadence IP block shouldn't it be named
> Cadence and made generic? Or is the frontend somehow SiFive specific?
For some reason I thought we had a SiFive-specific interface to this, but I may
have gotten that confused with something else as it's been a while. Someone
from SiFive would probably have a better idea, but it looks like the person I'd
ask isn't thereany more so I'm all out of options ;)
It looks like there was a very similar driver posted by Dhananjay Kangude from
Cadence in April: https://lkml.org/lkml/2020/4/6/358 . Some of the register
definitions seem to be different, but the code I looked at is very similar so
there's at least some bits that could be shared. I found a v4 of that patch
set, but that was back in May: https://lkml.org/lkml/2020/5/11/912 . It
alludes to a v5, but I can't find one. I've added Dhananjay, maybe he knows
what's up?
I don't know enough about the block to know if the subtle difference in
register names/offsets means. They look properly jumbled up (ie, not just an
offset), so maybe there's just different versions or that's the SiFive-specific
part I had bouncing around my head? Either way, it seems like one driver with
some simple configuration could handle both of these -- either sticking the
offsets in the DT (if they're going to be different everywhere) or by coming up
with some version sort of thing (if there's a handful of these).
I'm now also a bit worried about the provenace of this code. The two drivers
are errily similar -- for example, the variable definitions in handle_ce()
u64 err_c_addr = 0x0;
u64 err_c_data = 0x0;
u32 err_c_synd, err_c_id;
u32 sig_val_l, sig_val_h;
are exactly the same.
> -----Original Message-----
> From: Palmer Dabbelt <[email protected]>
> Sent: 09 September 2020 08:42
> To: Christoph Hellwig <[email protected]>; [email protected]
> Cc: Yash Shah <[email protected]>; [email protected]; Paul
> Walmsley ( Sifive) <[email protected]>; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; Sachin Ghadi
> <[email protected]>; [email protected];
> [email protected]; [email protected]; linux-
> [email protected]
> Subject: Re: [PATCH v2 2/3] soc: sifive: Add SiFive specific Cadence DDR
> controller driver
>
> [External Email] Do not click links or attachments unless you recognize the
> sender and know the content is safe
>
> On Sun, 06 Sep 2020 23:11:26 PDT (-0700), Christoph Hellwig wrote:
> > On Mon, Sep 07, 2020 at 11:17:58AM +0530, Yash Shah wrote:
> >> Add a driver to manage the Cadence DDR controller present on SiFive
> >> SoCs At present the driver manages the EDAC feature of the DDR
> controller.
> >> Additional features may be added to the driver in future to control
> >> other aspects of the DDR controller.
> >
> > So if this is a generic(ish) Cadence IP block shouldn't it be named
> > Cadence and made generic? Or is the frontend somehow SiFive specific?
>
> For some reason I thought we had a SiFive-specific interface to this, but I may
> have gotten that confused with something else as it's been a while. Someone
> from SiFive would probably have a better idea, but it looks like the person I'd
> ask isn't thereany more so I'm all out of options ;)
>
> It looks like there was a very similar driver posted by Dhananjay Kangude
> from Cadence in April: https://lkml.org/lkml/2020/4/6/358 . Some of the
> register definitions seem to be different, but the code I looked at is very
> similar so there's at least some bits that could be shared. I found a v4 of that
> patch set, but that was back in May: https://lkml.org/lkml/2020/5/11/912 . It
> alludes to a v5, but I can't find one. I've added Dhananjay, maybe he knows
> what's up?
>
I consulted with Dhananjay before posting this patch. From what I understood, Cadence provide highly configurable and customised DDR IP blocks based on the SoC vendor's need. This impacts the register configuration and probably the offsets too.
I had also refer the v4 patch posted by Dhananjay mentioned above and found that the registers offsets are not matching with that of Cadence DDR IP in SiFive SoC. Therefore it seems this DDR IP block has SiFive specific configurations and hence this Sifive specific driver.
> I don't know enough about the block to know if the subtle difference in
> register names/offsets means. They look properly jumbled up (ie, not just an
> offset), so maybe there's just different versions or that's the SiFive-specific
> part I had bouncing around my head? Either way, it seems like one driver
> with some simple configuration could handle both of these -- either sticking
> the offsets in the DT (if they're going to be different everywhere) or by
> coming up with some version sort of thing (if there's a handful of these).
>
> I'm now also a bit worried about the provenace of this code. The two drivers
> are errily similar -- for example, the variable definitions in handle_ce()
>
> u64 err_c_addr = 0x0;
> u64 err_c_data = 0x0;
> u32 err_c_synd, err_c_id;
> u32 sig_val_l, sig_val_h;
>
> are exactly the same.
I apologized, I forgot to mention it in cover-letter. I have based my work on Dhananjay's v4 patch[0].
- Yash
[0]: https://lkml.org/lkml/2020/4/24/183
On Tue, Sep 08, 2020 at 08:12:16PM -0700, Palmer Dabbelt wrote:
> I don't know enough about the block to know if the subtle difference in
> register names/offsets means. They look properly jumbled up (ie, not just an
> offset), so maybe there's just different versions or that's the SiFive-specific
> part I had bouncing around my head? Either way, it seems like one driver with
> some simple configuration could handle both of these -- either sticking the
> offsets in the DT (if they're going to be different everywhere) or by coming up
> with some version sort of thing (if there's a handful of these).
regmap can be used to handle non-uniform register layouts for the same
functionality.
On Tue, 08 Sep 2020 23:00:45 PDT (-0700), Christoph Hellwig wrote:
> On Tue, Sep 08, 2020 at 08:12:16PM -0700, Palmer Dabbelt wrote:
>> I don't know enough about the block to know if the subtle difference in
>> register names/offsets means. They look properly jumbled up (ie, not just an
>> offset), so maybe there's just different versions or that's the SiFive-specific
>> part I had bouncing around my head? Either way, it seems like one driver with
>> some simple configuration could handle both of these -- either sticking the
>> offsets in the DT (if they're going to be different everywhere) or by coming up
>> with some version sort of thing (if there's a handful of these).
>
> regmap can be used to handle non-uniform register layouts for the same
> functionality.
Ah, cool, I hadn't seen that before. That seems like the way to go if this is
truly an implementatic-specific register mapping. As I was falling asleep last
night I remembered that we did end up with implementation-specific register
maps for some of the IP we integrated. That was usually the case for IP where
we had some signals that we just didn't know what to do with, and while I know
the DDR integration was a real trip I'm not sure if that's where these
registers came from.
Hopefully someone who has better access to these hardware implementations can
comment.
On Mon, Sep 07, 2020 at 11:17:56AM +0530, Yash Shah wrote:
> The series add supports for SiFive DDR controller driver. This driver
> is use to manage the Cadence DDR controller present in SiFive SoCs.
> Currently it manages only the EDAC feature of the DDR controller.
> The series also adds Memory controller EDAC support for SiFive platform.
> It register for notifier event from SiFive DDR controller driver.
This is an odd split and notifiers aren't a great interface. Why not
just combine these? Is there some other DDR controller functionality
planned for the driver?
FYI, highbank_mc_edac.c is also a Cadence controller. IIRC, the register
layout changes for every customer/design.
Rob
On Mon, Sep 07, 2020 at 11:17:57AM +0530, Yash Shah wrote:
> Add device tree bindings for SiFive FU540 DDR controller driver
>
> Signed-off-by: Yash Shah <[email protected]>
> Reviewed-by: Palmer Dabbelt <[email protected]>
> Acked-by: Palmer Dabbelt <[email protected]>
> ---
> .../devicetree/bindings/riscv/sifive-ddr.yaml | 41 ++++++++++++++++++++++
Bindings are organized by function, not vendor/arch generally. This goes
in bindings/memory-controllers/.
> 1 file changed, 41 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/riscv/sifive-ddr.yaml
>
> diff --git a/Documentation/devicetree/bindings/riscv/sifive-ddr.yaml b/Documentation/devicetree/bindings/riscv/sifive-ddr.yaml
> new file mode 100644
> index 0000000..0288119
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/riscv/sifive-ddr.yaml
> @@ -0,0 +1,41 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/riscv/sifive-ddr.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: SiFive DDR memory controller binding
> +
> +description: |
> + The Sifive DDR controller driver is used to manage the Cadence DDR
> + controller present in SiFive FU540-C000 SoC. Currently the driver is
> + used to manage EDAC feature of the DDR controller.
Bindings describe h/w not drivers. What a driver supports is irrelevant.
> +
> +maintainers:
> + - Yash Shah <[email protected]>
> +
> +properties:
> + compatible:
> + enum:
> + - sifive,fu540-c000-ddr
> +
> + reg:
> + maxItems: 1
> +
> + interrupts:
> + maxItems: 1
> +
> +required:
> + - compatible
> + - reg
> + - interrupts
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + memory-controller@100b0000 {
> + compatible = "sifive,fu540-c000-ddr";
> + reg = <0x100b0000 0x4000>;
> + interrupts = <31>;
> + };
> --
> 2.7.4
>
> -----Original Message-----
> From: Palmer Dabbelt <[email protected]>
> Sent: Wednesday, September 9, 2020 8:42 AM
> To: Christoph Hellwig <[email protected]>; Dhananjay Vilasrao Kangude
> <[email protected]>
> Cc: [email protected]; [email protected]; Paul Walmsley
> <[email protected]>; [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected];
> [email protected]; [email protected]; linux-
> [email protected]; [email protected]
> Subject: Re: [PATCH v2 2/3] soc: sifive: Add SiFive specific Cadence DDR
> controller driver
>
> EXTERNAL MAIL
>
>
> On Sun, 06 Sep 2020 23:11:26 PDT (-0700), Christoph Hellwig wrote:
> > On Mon, Sep 07, 2020 at 11:17:58AM +0530, Yash Shah wrote:
> >> Add a driver to manage the Cadence DDR controller present on SiFive
> >> SoCs At present the driver manages the EDAC feature of the DDR
> controller.
> >> Additional features may be added to the driver in future to control
> >> other aspects of the DDR controller.
> >
> > So if this is a generic(ish) Cadence IP block shouldn't it be named
> > Cadence and made generic? Or is the frontend somehow SiFive specific?
>
> For some reason I thought we had a SiFive-specific interface to this, but I may
> have gotten that confused with something else as it's been a while. Someone
> from SiFive would probably have a better idea, but it looks like the person I'd
> ask isn't thereany more so I'm all out of options ;)
>
> It looks like there was a very similar driver posted by Dhananjay Kangude
> from Cadence in April:
> https://urldefense.com/v3/__https://lkml.org/lkml/2020/4/6/358__;!!EHscm
> S1ygiU1lA!UfVYWzQqCgaUNKN156ffKM5NkFoYtPhHapruC3yqme7nvbUBnD2
> mEHg8F6it4y4$ . Some of the register definitions seem to be different, but
> the code I looked at is very similar so there's at least some bits that could be
> shared. I found a v4 of that patch set, but that was back in May:
> https://urldefense.com/v3/__https://lkml.org/lkml/2020/5/11/912__;!!EHsc
> mS1ygiU1lA!UfVYWzQqCgaUNKN156ffKM5NkFoYtPhHapruC3yqme7nvbUBnD
> 2mEHg8DeCwApk$ . It alludes to a v5, but I can't find one. I've added
> Dhananjay, maybe he knows what's up?
>
> I don't know enough about the block to know if the subtle difference in
> register names/offsets means. They look properly jumbled up (ie, not just an
> offset), so maybe there's just different versions or that's the SiFive-specific
> part I had bouncing around my head? Either way, it seems like one driver
> with some simple configuration could handle both of these -- either sticking
> the offsets in the DT (if they're going to be different everywhere) or by
> coming up with some version sort of thing (if there's a handful of these).
>
> I'm now also a bit worried about the provenace of this code. The two drivers
> are errily similar -- for example, the variable definitions in handle_ce()
>
> u64 err_c_addr = 0x0;
> u64 err_c_data = 0x0;
> u32 err_c_synd, err_c_id;
> u32 sig_val_l, sig_val_h;
>
> are exactly the same.
[Dhananjay Kangude]
Hi Palmer,
Sorry for delayed reply.
I was expecting new changes into the hardware IP since last couple of
months thus I haven't up streamed V5 patch till now. The cadence driver version
is of more generic for cadence DDR controllers which could be part of other SoCs too.
I would suggest Yash to patch Sifive specific changes once cadence DDR controller driver
get up streamed. I will send V5 in coming days.
Thank,
Dhananjay
On Mon, Sep 07, 2020 at 11:17:59AM +0530, Yash Shah wrote:
> Add Memory controller EDAC support to the SiFive platform EDAC driver.
> It registers for ECC notifier events from the memory controller.
>
> Signed-off-by: Yash Shah <[email protected]>
> Reviewed-by: Palmer Dabbelt <[email protected]>
> Acked-by: Palmer Dabbelt <[email protected]>
Reviewed-by is usually enough and stronger than Acked-by. See sections
12) When to use Acked-by:, Cc:, and Co-developed-by:
13) Using Reported-by:, Tested-by:, Reviewed-by:, Suggested-by: and Fixes:
in Documentation/process/submitting-patches.rst.
With that addressed:
Acked-by: Borislav Petkov <[email protected]>
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette