Re: [PATCH v7 4/5] remoteproc: ingenic: Added remoteproc driver
From: Paul Cercueil
Date: Thu Jun 11 2020 - 18:21:33 EST
Hi Suman,
Le jeu. 11 juin 2020 à 16:47, Suman Anna <s-anna@xxxxxx> a écrit :
Hi Paul,
On 5/15/20 5:43 AM, Paul Cercueil wrote:
This driver is used to boot, communicate with and load firmwares to
the
MIPS co-processor found in the VPU hardware of the JZ47xx SoCs from
Ingenic.
I have a few comments w.r.t pm_runtime usage in this driver.
Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
Acked-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
---
Notes:
v2: Remove exception for always-mapped memories
v3: - Use clk_bulk API
- Move device-managed code to its own patch [3/4]
- Move devicetree table right above ingenic_rproc_driver
- Removed #ifdef CONFIG_OF around devicetree table
- Removed .owner = THIS_MODULE in ingenic_rproc_driver
- Removed useless platform_set_drvdata()
v4: - Add fix reported by Julia
- Change Kconfig symbol to INGENIC_VPU_RPROC
- Add documentation to struct vpu
- disable_irq_nosync() -> disable_irq()
v5: No change
v6: Instead of prepare/unprepare callbacks, use PM runtime
callbacks
v7: - Remove use of of_match_ptr()
- Move Kconfig symbol so that it's in alphabetical order
- Add missing doc for private structure field aux_base
- Don't check for (len <= 0) in da_to_va()
- Add missing \n in dev_info/dev_err messages
drivers/remoteproc/Kconfig | 9 +
drivers/remoteproc/Makefile | 1 +
drivers/remoteproc/ingenic_rproc.c | 280
+++++++++++++++++++++++++++++
3 files changed, 290 insertions(+)
create mode 100644 drivers/remoteproc/ingenic_rproc.c
diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig
index fbaed079b299..c4d1731295eb 100644
--- a/drivers/remoteproc/Kconfig
+++ b/drivers/remoteproc/Kconfig
@@ -23,6 +23,15 @@ config IMX_REMOTEPROC
It's safe to say N here.
+config INGENIC_VPU_RPROC
+ tristate "Ingenic JZ47xx VPU remoteproc support"
+ depends on MIPS || COMPILE_TEST
+ help
+ Say y or m here to support the VPU in the JZ47xx SoCs from
Ingenic.
+
+ This can be either built-in or a loadable module.
+ If unsure say N.
+
config MTK_SCP
tristate "Mediatek SCP support"
depends on ARCH_MEDIATEK
diff --git a/drivers/remoteproc/Makefile
b/drivers/remoteproc/Makefile
index 0effd3825035..e8b886e511f0 100644
--- a/drivers/remoteproc/Makefile
+++ b/drivers/remoteproc/Makefile
@@ -10,6 +10,7 @@ remoteproc-y += remoteproc_sysfs.o
remoteproc-y += remoteproc_virtio.o
remoteproc-y += remoteproc_elf_loader.o
obj-$(CONFIG_IMX_REMOTEPROC) += imx_rproc.o
+obj-$(CONFIG_INGENIC_VPU_RPROC) += ingenic_rproc.o
obj-$(CONFIG_MTK_SCP) += mtk_scp.o mtk_scp_ipi.o
obj-$(CONFIG_OMAP_REMOTEPROC) += omap_remoteproc.o
obj-$(CONFIG_WKUP_M3_RPROC) += wkup_m3_rproc.o
diff --git a/drivers/remoteproc/ingenic_rproc.c
b/drivers/remoteproc/ingenic_rproc.c
new file mode 100644
index 000000000000..189020d77b25
--- /dev/null
+++ b/drivers/remoteproc/ingenic_rproc.c
@@ -0,0 +1,280 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Ingenic JZ47xx remoteproc driver
+ * Copyright 2019, Paul Cercueil <paul@xxxxxxxxxxxxxxx>
+ */
+
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/remoteproc.h>
+
+#include "remoteproc_internal.h"
+
+#define REG_AUX_CTRL 0x0
+#define REG_AUX_MSG_ACK 0x10
+#define REG_AUX_MSG 0x14
+#define REG_CORE_MSG_ACK 0x18
+#define REG_CORE_MSG 0x1C
+
+#define AUX_CTRL_SLEEP BIT(31)
+#define AUX_CTRL_MSG_IRQ_EN BIT(3)
+#define AUX_CTRL_NMI_RESETS BIT(2)
+#define AUX_CTRL_NMI BIT(1)
+#define AUX_CTRL_SW_RESET BIT(0)
+
+struct vpu_mem_map {
+ const char *name;
+ unsigned int da;
+};
+
+struct vpu_mem_info {
+ const struct vpu_mem_map *map;
+ unsigned long len;
+ void __iomem *base;
+};
+
+static const struct vpu_mem_map vpu_mem_map[] = {
+ { "tcsm0", 0x132b0000 },
+ { "tcsm1", 0xf4000000 },
+ { "sram", 0x132f0000 },
+};
+
+/**
+ * struct vpu - Ingenic VPU remoteproc private structure
+ * @irq: interrupt number
+ * @clks: pointers to the VPU and AUX clocks
+ * @aux_base: raw pointer to the AUX interface registers
+ * @mem_info: array of struct vpu_mem_info, which contain the
mapping info of
+ * each of the external memories
+ * @dev: private pointer to the device
+ */
+struct vpu {
+ int irq;
+ struct clk_bulk_data clks[2];
+ void __iomem *aux_base;
+ struct vpu_mem_info mem_info[ARRAY_SIZE(vpu_mem_map)];
+ struct device *dev;
+};
+
+static int ingenic_rproc_start(struct rproc *rproc)
+{
+ struct vpu *vpu = rproc->priv;
+ u32 ctrl;
+
+ enable_irq(vpu->irq);
+
+ /* Reset the AUX and enable message IRQ */
+ ctrl = AUX_CTRL_NMI_RESETS | AUX_CTRL_NMI | AUX_CTRL_MSG_IRQ_EN;
+ writel(ctrl, vpu->aux_base + REG_AUX_CTRL);
+
+ return 0;
+}
+
+static int ingenic_rproc_stop(struct rproc *rproc)
+{
+ struct vpu *vpu = rproc->priv;
+
+ disable_irq(vpu->irq);
+
+ /* Keep AUX in reset mode */
+ writel(AUX_CTRL_SW_RESET, vpu->aux_base + REG_AUX_CTRL);
+
+ return 0;
+}
+
+static void ingenic_rproc_kick(struct rproc *rproc, int vqid)
+{
+ struct vpu *vpu = rproc->priv;
+
+ writel(vqid, vpu->aux_base + REG_CORE_MSG);
+}
+
+static void *ingenic_rproc_da_to_va(struct rproc *rproc, u64 da,
size_t len)
+{
+ struct vpu *vpu = rproc->priv;
+ void __iomem *va = NULL;
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE(vpu_mem_map); i++) {
+ const struct vpu_mem_info *info = &vpu->mem_info[i];
+ const struct vpu_mem_map *map = info->map;
+
+ if (da >= map->da && (da + len) < (map->da + info->len)) {
+ va = info->base + (da - map->da);
+ break;
+ }
+ }
+
+ return (__force void *)va;
+}
+
+static struct rproc_ops ingenic_rproc_ops = {
+ .start = ingenic_rproc_start,
+ .stop = ingenic_rproc_stop,
+ .kick = ingenic_rproc_kick,
+ .da_to_va = ingenic_rproc_da_to_va,
+};
+
+static irqreturn_t vpu_interrupt(int irq, void *data)
+{
+ struct rproc *rproc = data;
+ struct vpu *vpu = rproc->priv;
+ u32 vring;
+
+ vring = readl(vpu->aux_base + REG_AUX_MSG);
+
+ /* Ack the interrupt */
+ writel(0, vpu->aux_base + REG_AUX_MSG_ACK);
+
+ return rproc_vq_interrupt(rproc, vring);
+}
+
+static void ingenic_rproc_disable_clks(void *data)
+{
+ struct vpu *vpu = data;
+
+ pm_runtime_resume(vpu->dev);
+ pm_runtime_disable(vpu->dev);
+
+ clk_bulk_disable_unprepare(ARRAY_SIZE(vpu->clks), vpu->clks);
+}
+
+static int ingenic_rproc_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct resource *mem;
+ struct rproc *rproc;
+ struct vpu *vpu;
+ unsigned int i;
+ int ret;
+
+ rproc = devm_rproc_alloc(dev, "ingenic-vpu",
+ &ingenic_rproc_ops, NULL, sizeof(*vpu));
+ if (!rproc)
+ return -ENOMEM;
+
+ vpu = rproc->priv;
+ vpu->dev = &pdev->dev;
+ platform_set_drvdata(pdev, vpu);
+
+ mem = platform_get_resource_byname(pdev, IORESOURCE_MEM, "aux");
+ vpu->aux_base = devm_ioremap_resource(dev, mem);
+ if (IS_ERR(vpu->aux_base)) {
+ dev_err(dev, "Failed to ioremap\n");
+ return PTR_ERR(vpu->aux_base);
+ }
+
+ for (i = 0; i < ARRAY_SIZE(vpu_mem_map); i++) {
+ mem = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+ vpu_mem_map[i].name);
+
+ vpu->mem_info[i].base = devm_ioremap_resource(dev, mem);
+ if (IS_ERR(vpu->mem_info[i].base)) {
+ ret = PTR_ERR(vpu->mem_info[i].base);
+ dev_err(dev, "Failed to ioremap\n");
+ return ret;
+ }
+
+ vpu->mem_info[i].len = resource_size(mem);
+ vpu->mem_info[i].map = &vpu_mem_map[i];
+ }
+
+ vpu->clks[0].id = "vpu";
+ vpu->clks[1].id = "aux";
+
+ ret = devm_clk_bulk_get(dev, ARRAY_SIZE(vpu->clks), vpu->clks);
+ if (ret) {
+ dev_err(dev, "Failed to get clocks\n");
+ return ret;
+ }
+
+ vpu->irq = platform_get_irq(pdev, 0);
+ if (vpu->irq < 0)
+ return vpu->irq;
+
+ ret = devm_request_irq(dev, vpu->irq, vpu_interrupt, 0, "VPU",
rproc);
+ if (ret < 0) {
+ dev_err(dev, "Failed to request IRQ\n");
+ return ret;
+ }
+
+ disable_irq(vpu->irq);
+
+ /* The clocks must be enabled for the firmware to be loaded in
TCSM */
+ ret = clk_bulk_prepare_enable(ARRAY_SIZE(vpu->clks), vpu->clks);
+ if (ret) {
+ dev_err(dev, "Unable to start clocks\n");
+ return ret;
+ }
You are enabling the clocks directly here and also trying to manage
them through pm_runtime callbacks again.
Yes. The clocks need to be enabled in the probe.
+
+ pm_runtime_irq_safe(dev);
Nothing wrong with this, but this does take an additional reference
count on the parent device (a bus device for you??), and also implies
that your clk driver code can all run in atomic context so unless you
have a strong reason, it is safe to drop this.
The clock driver code can run in atomic context, it is guaranteed by
the clk API.
+ pm_runtime_set_active(dev);
The get_sync below would have been sufficient if you had either
limited the clk API above to just clk_prepare, or you could have
moved the whole clk API above into your runtime resume callback.
You assume that pm_runtime_get() will enable the clocks, but that's
only true if CONFIG_PM is set.
The reason the clocks are enabled in the probe, and
pm_runtime_set_active() is called, is that it works whether or not
CONFIG_PM is set.
+ pm_runtime_enable(dev);
+ pm_runtime_get_sync(dev);
If the intention was to increment the usage count with the above
sequence, pm_runtime_get_noresume() is better. But dropping all of
the above and just using get_sync would have been sufficient.
+ pm_runtime_use_autosuspend(dev);
I don't see any setting of the autosuspend delay (default value is
0). So, you might have as well just not used this at all, and just
used pm_runtime_put() below.
Autosuspend delay value can be set from userspace.
+
+ ret = devm_add_action_or_reset(dev, ingenic_rproc_disable_clks,
vpu);
+ if (ret) {
+ dev_err(dev, "Unable to register action\n");
+ goto out_pm_put;
+ }
+
+ ret = devm_rproc_add(dev, rproc);
+ if (ret) {
+ dev_err(dev, "Failed to register remote processor\n");
+ goto out_pm_put;
+ }
You are using auto-boot, so the firmware loading is an asynchronous
event and most probably you would run through below sequence first,
and end up disabling the clocks with an incorrect rpm status.
The driver can auto-load the firmware, but that does not mean it will.
We actually don't do that, and load a task-specific firmware onto the
remote processor on demand.
+
+out_pm_put:
+ pm_runtime_put_autosuspend(dev);
And finally, with the remoteproc core rpm patch, this would all have
been unnecessary.
+
+ return ret;
+}
+
+static const struct of_device_id ingenic_rproc_of_matches[] = {
+ { .compatible = "ingenic,jz4770-vpu-rproc", },
+ {}
+};
+MODULE_DEVICE_TABLE(of, ingenic_rproc_of_matches);
+
+static int __maybe_unused ingenic_rproc_suspend(struct device *dev)
+{
+ struct vpu *vpu = dev_get_drvdata(dev);
+
+ clk_bulk_disable(ARRAY_SIZE(vpu->clks), vpu->clks);
+
+ return 0;
+}
+
+static int __maybe_unused ingenic_rproc_resume(struct device *dev)
+{
+ struct vpu *vpu = dev_get_drvdata(dev);
+
+ return clk_bulk_enable(ARRAY_SIZE(vpu->clks), vpu->clks);
+}
+
+static const struct dev_pm_ops __maybe_unused ingenic_rproc_pm = {
+ SET_RUNTIME_PM_OPS(ingenic_rproc_suspend, ingenic_rproc_resume,
NULL)
+};
+
+static struct platform_driver ingenic_rproc_driver = {
+ .probe = ingenic_rproc_probe,
+ .driver = {
+ .name = "ingenic-vpu",
+#ifdef CONFIG_PM
Not sure why you would want to maintain this conditional, because
runtime_pm is a core dependency now for your driver to work properly.
No, it is not - the driver works perfectly fine with CONFIG_PM being
disabled, and having a hardcoded dependency on CONFIG_PM is not
something we want.
Cheers,
-Paul
regards
Suman
+ .pm = &ingenic_rproc_pm,
+#endif
+ .of_match_table = ingenic_rproc_of_matches,
+ },
+};
+module_platform_driver(ingenic_rproc_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Paul Cercueil <paul@xxxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("Ingenic JZ47xx Remote Processor control
driver");