Re: [PATCH v5 1/3] mmc: dw_mmc-bluefield: Add driver extension
From: Shawn Lin
Date: Thu May 03 2018 - 03:25:30 EST
On 2018/5/2 20:45, Liming Sun wrote:
Please see response inline.
Thanks,
Liming
-----Original Message-----
From: Shawn Lin [mailto:shawn.lin@xxxxxxxxxxxxxx]
Sent: Tuesday, May 1, 2018 9:02 PM
To: Liming Sun <lsun@xxxxxxxxxxxx>; Mark Rutland
<mark.rutland@xxxxxxx>; Jaehoon Chung <jh80.chung@xxxxxxxxxxx>;
Catalin Marinas <catalin.marinas@xxxxxxx>; Will Deacon
<will.deacon@xxxxxxx>
Cc: Ulf Hansson <ulf.hansson@xxxxxxxxxx>; Rob Herring
<robh+dt@xxxxxxxxxx>; shawn.lin@xxxxxxxxxxxxxx; linux-
mmc@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux-
kernel@xxxxxxxxxxxxxxx; stable@xxxxxxxxxx
Subject: Re: [PATCH v5 1/3] mmc: dw_mmc-bluefield: Add driver extension
On 2018/5/2 2:19, Liming Sun wrote:
This commit adds extension to the dw_mmc driver for Mellanox BlueField
SoC. It updates the UHS_REG_EXT register to bring up the eMMC card on
this SoC.
Cc: stable@xxxxxxxxxx
Why?
[Liming] This is recommended value from HW team. Without this setting, the eMMC
controller and cards can be found in Linux, but not stable. Writing to it could caused
CRC error.
Well, I refered to the "Cc: stable@xxxxxxxxxx" in the commit msg.
Signed-off-by: Liming Sun <lsun@xxxxxxxxxxxx>
Reviewed-by: David Woods <dwoods@xxxxxxxxxxxx>
---
drivers/mmc/host/Kconfig | 9 +++++
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/dw_mmc-bluefield.c | 72
+++++++++++++++++++++++++++++++++++++
3 files changed, 82 insertions(+)
create mode 100644 drivers/mmc/host/dw_mmc-bluefield.c
diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index 9589f9c..26ac6b5 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -717,6 +717,15 @@ config MMC_DW_K3
Synopsys DesignWare Memory Card Interface driver. Select this
option
for platforms based on Hisilicon K3 SoC's.
+config MMC_DW_BLUEFIELD
And did you have feedback of my comment in V2？
http://lists-archives.com/linux-kernel/29104830-mmc-dw_mmc-bluefield-
add-driver-extension.html
+ tristate "BlueField specific extensions for Synopsys DW Memory Card
Interface"
+ depends on MMC_DW
+ select MMC_DW_PLTFM
+ help
+ This selects support for Mellanox BlueField SoC specific extensions
to
+ the Synopsys DesignWare Memory Card Interface driver. Select this
+ option for platforms based on Mellanox BlueField SoC's.
+
config MMC_DW_PCI
tristate "Synopsys Designware MCI support on PCI bus"
depends on MMC_DW && PCI
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index 6aead24..267b3f1 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -55,6 +55,7 @@ obj-$(CONFIG_MMC_DW_K3) += dw_mmc-
k3.o
obj-$(CONFIG_MMC_DW_PCI) += dw_mmc-pci.o
obj-$(CONFIG_MMC_DW_ROCKCHIP) += dw_mmc-rockchip.o
obj-$(CONFIG_MMC_DW_ZX) += dw_mmc-zx.o
+obj-$(CONFIG_MMC_DW_BLUEFIELD) += dw_mmc-bluefield.o
obj-$(CONFIG_MMC_SH_MMCIF) += sh_mmcif.o
obj-$(CONFIG_MMC_JZ4740) += jz4740_mmc.o
obj-$(CONFIG_MMC_VUB300) += vub300.o
diff --git a/drivers/mmc/host/dw_mmc-bluefield.c
b/drivers/mmc/host/dw_mmc-bluefield.c
new file mode 100644
index 0000000..12067b1
--- /dev/null
+++ b/drivers/mmc/host/dw_mmc-bluefield.c
@@ -0,0 +1,72 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018 Mellanox Technologies.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/mmc.h>
+#include <linux/of.h>
+
+#include "dw_mmc.h"
+#include "dw_mmc-pltfm.h"
+
+static void dw_mci_bluefield_set_ios(struct dw_mci *host, struct
mmc_ios *ios)
+{
+ u32 regs;
+
+ /* Set drive=4 (bit 29:23) and sample=2 (bit 22:16) in UHS_REG_EXT.
*/
+ regs = mci_readl(host, UHS_REG_EXT);
+ regs = (regs & ~0x3F100000 & ~0x7F0000) | (4 << 23) | (2 << 16);
+ mci_writel(host, UHS_REG_EXT, regs);
+}
+
+static const struct dw_mci_drv_data bluefield_drv_data = {
+ .set_ios = dw_mci_bluefield_set_ios
+};
+
+static const struct of_device_id dw_mci_bluefield_match[] = {
+ { .compatible = "mellanox,bluefield-dw-mshc",
+ .data = &bluefield_drv_data },
+ {},
+};
+MODULE_DEVICE_TABLE(of, dw_mci_bluefield_match);
+
+static int dw_mci_bluefield_probe(struct platform_device *pdev)
+{
+ const struct dw_mci_drv_data *drv_data = NULL;
+ const struct of_device_id *match;
+
+ if (pdev->dev.of_node) {
+ match = of_match_node(dw_mci_bluefield_match,
+ pdev->dev.of_node);
+ drv_data = match->data;
+ }
+
+ return dw_mci_pltfm_register(pdev, drv_data);
+}
+
+static struct platform_driver dw_mci_bluefield_pltfm_driver = {
+ .probe = dw_mci_bluefield_probe,
+ .remove = dw_mci_pltfm_remove,
+ .driver = {
+ .name = "dwmmc_bluefield",
+ .of_match_table = dw_mci_bluefield_match,
+ .pm = &dw_mci_pltfm_pmops,
+ },
+};
+
+module_platform_driver(dw_mci_bluefield_pltfm_driver);
+
+MODULE_DESCRIPTION("BlueField DW Multimedia Card driver");
+MODULE_AUTHOR("Mellanox Technologies");
+MODULE_LICENSE("GPL v2");