[U-Boot] [PATCHv1 2/4] dm: cache: Create a uclass for cache controller

Dinh Nguyen dinguyen at kernel.org
Fri Mar 8 16:16:49 UTC 2019


The cache controller driver configures the cache settings that can be
found in the device tree files.

This initial revision only configures basic settings(data & instruction
prefetch, shared-override, data & tag latency). I believe these are the
settings that affect performance the most. Comprehensive settings can be
done by the OS.

Signed-off-by: Dinh Nguyen <dinguyen at kernel.org>
---
 drivers/Kconfig              |  2 +
 drivers/Makefile             |  1 +
 drivers/cache/Kconfig        | 22 ++++++++++
 drivers/cache/Makefile       |  3 ++
 drivers/cache/cache-l2x0.c   | 82 ++++++++++++++++++++++++++++++++++++
 drivers/cache/cache-uclass.c | 13 ++++++
 include/dm/uclass-id.h       |  1 +
 7 files changed, 124 insertions(+)
 create mode 100644 drivers/cache/Kconfig
 create mode 100644 drivers/cache/Makefile
 create mode 100644 drivers/cache/cache-l2x0.c
 create mode 100644 drivers/cache/cache-uclass.c

diff --git a/drivers/Kconfig b/drivers/Kconfig
index f24351ac4f..842201b753 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -14,6 +14,8 @@ source "drivers/block/Kconfig"
 
 source "drivers/bootcount/Kconfig"
 
+source "drivers/cache/Kconfig"
+
 source "drivers/clk/Kconfig"
 
 source "drivers/cpu/Kconfig"
diff --git a/drivers/Makefile b/drivers/Makefile
index a7bba3ed56..0a00096332 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -77,6 +77,7 @@ obj-$(CONFIG_BIOSEMU) += bios_emulator/
 obj-y += block/
 obj-y += board/
 obj-$(CONFIG_BOOTCOUNT_LIMIT) += bootcount/
+obj-y += cache/
 obj-$(CONFIG_CPU) += cpu/
 obj-y += crypto/
 obj-$(CONFIG_FASTBOOT) += fastboot/
diff --git a/drivers/cache/Kconfig b/drivers/cache/Kconfig
new file mode 100644
index 0000000000..d6b2b6762a
--- /dev/null
+++ b/drivers/cache/Kconfig
@@ -0,0 +1,22 @@
+#
+# Cache controllers
+#
+
+menu "Cache Controller drivers"
+
+config CACHE
+	bool "Enable Driver Model for Cache drivers"
+	depends on DM
+	help
+	  Enable driver model for cache controllers.
+
+config L2X0_CACHE
+	tristate "PL310 cache driver"
+	select CACHE
+	depends on ARM
+	help
+	  This driver is for the PL310 cache controller commonly found on
+	  ARMv7(32-bit) devices. The driver configures the cache settings
+	  found in the device tree.
+
+endmenu
diff --git a/drivers/cache/Makefile b/drivers/cache/Makefile
new file mode 100644
index 0000000000..fca37de0a8
--- /dev/null
+++ b/drivers/cache/Makefile
@@ -0,0 +1,3 @@
+
+obj-$(CONFIG_CACHE) += cache-uclass.o
+obj-$(CONFIG_L2X0_CACHE) += cache-l2x0.o
diff --git a/drivers/cache/cache-l2x0.c b/drivers/cache/cache-l2x0.c
new file mode 100644
index 0000000000..cdd6ddb59b
--- /dev/null
+++ b/drivers/cache/cache-l2x0.c
@@ -0,0 +1,82 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 Intel Corporation <www.intel.com>
+ */
+#include <common.h>
+#include <command.h>
+#include <dm.h>
+
+#include <asm/io.h>
+#include <asm/pl310.h>
+
+static void l2c310_of_parse(struct udevice *dev)
+{
+	u32 tag[3] = { 0, 0, 0 };
+	u32 saved_reg, prefetch;
+	int ret;
+	struct pl310_regs *regs = (struct pl310_regs *)devfdt_get_addr(dev);
+
+	/*Disable the L2 Cache */
+	clrbits_le32(&regs->pl310_ctrl, L2X0_CTRL_EN);
+
+	saved_reg = readl(&regs->pl310_aux_ctrl);
+	if (dev_read_u32(dev, "prefetch-data", &prefetch) == 0) {
+		if (prefetch)
+			saved_reg |= L310_AUX_CTRL_DATA_PREFETCH_MASK;
+		else
+			saved_reg &= ~L310_AUX_CTRL_DATA_PREFETCH_MASK;
+	}
+
+	if (dev_read_u32(dev, "prefetch-instr", &prefetch) == 0) {
+		if (prefetch)
+			saved_reg |= L310_AUX_CTRL_INST_PREFETCH_MASK;
+		else
+			saved_reg &= ~L310_AUX_CTRL_INST_PREFETCH_MASK;
+	}
+
+	saved_reg |= dev_read_bool(dev, "arm,shared-override");
+	writel(saved_reg, &regs->pl310_aux_ctrl);
+
+	saved_reg = readl(&regs->pl310_tag_latency_ctrl);
+	if (dev_read_u32_array(dev, "arm,tag-latency", tag, 3) == 0)
+		saved_reg |= L310_LATENCY_CTRL_RD(tag[0] - 1) |
+			     L310_LATENCY_CTRL_WR(tag[1] - 1) |
+			     L310_LATENCY_CTRL_SETUP(tag[2] - 1);
+	writel(saved_reg, &regs->pl310_tag_latency_ctrl);
+
+	saved_reg = readl(&regs->pl310_data_latency_ctrl);
+	if (dev_read_u32_array(dev, "arm,data-latency", tag, 3) == 0)
+		saved_reg |= L310_LATENCY_CTRL_RD(tag[0] - 1) |
+			     L310_LATENCY_CTRL_WR(tag[1] - 1) |
+			     L310_LATENCY_CTRL_SETUP(tag[2] - 1);
+	writel(saved_reg, &regs->pl310_data_latency_ctrl);
+
+	/* Enable the L2 cache */
+	setbits_le32(&regs->pl310_ctrl, L2X0_CTRL_EN);
+}
+
+static int l2x0_ofdata_to_platdata(struct udevice *dev)
+{
+	return 0;
+}
+
+static int l2x0_probe(struct udevice *dev)
+{
+	l2c310_of_parse(dev);
+	return 0;
+}
+
+
+static const struct udevice_id l2x0_ids[] = {
+	{ .compatible = "arm,pl310-cache" },
+	{}
+};
+
+U_BOOT_DRIVER(pl310_cache) = {
+	.name   = "pl310_cache",
+	.id     = UCLASS_CACHE,
+	.of_match = l2x0_ids,
+	.probe	= l2x0_probe,
+	.ofdata_to_platdata = l2x0_ofdata_to_platdata,
+	.flags  = DM_FLAG_PRE_RELOC,
+};
diff --git a/drivers/cache/cache-uclass.c b/drivers/cache/cache-uclass.c
new file mode 100644
index 0000000000..27c1706bc1
--- /dev/null
+++ b/drivers/cache/cache-uclass.c
@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright Intel
+ */
+
+#include <common.h>
+#include <dm.h>
+
+UCLASS_DRIVER(cache) = {
+	.id		= UCLASS_CACHE,
+	.name		= "cache",
+	.post_bind	= dm_scan_fdt_dev,
+};
diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
index 86e59781b0..b0eef19be7 100644
--- a/include/dm/uclass-id.h
+++ b/include/dm/uclass-id.h
@@ -34,6 +34,7 @@ enum uclass_id {
 	UCLASS_BLK,		/* Block device */
 	UCLASS_BOARD,		/* Device information from hardware */
 	UCLASS_BOOTCOUNT,       /* Bootcount backing store */
+	UCLASS_CACHE,		/* Cache controller*/
 	UCLASS_CLK,		/* Clock source, e.g. used by peripherals */
 	UCLASS_CPU,		/* CPU, typically part of an SoC */
 	UCLASS_CROS_EC,		/* Chrome OS EC */
-- 
2.20.0



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