RE: [PATCH] soc: fsl: add DPAA2 console support

[Leo Li <leoyang.li@nxp.com>]

> -----Original Message-----
> From: Ioana Ciornei
> Sent: Thursday, April 4, 2019 5:48 AM
> To: Leo Li <leoyang.li@nxp.com>
> Cc: linux-kernel@vger.kernel.org; Roy Pledge <roy.pledge@nxp.com>
> Subject: Re: [PATCH] soc: fsl: add DPAA2 console support
> 
> On 4/3/19 10:55 PM, Li Yang wrote:
> > On Tue, Mar 26, 2019 at 2:17 PM Ioana Ciornei <ioana.ciornei@nxp.com>
> wrote:
> >>
> >> This patch adds DPAA2 MC and AIOP console log support.
> >>
> >> The platform driver probes on the "fsl,dpaa2-console" device tree
> >> node which describes the base firmware address needed in order to
> >> infer the start address of both firmware logs: MC and AIOP.
> >> It then exports two misc char devices which can be used to dump the
> >> needed logs.
> >>
> >> Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
> >> Signed-off-by: Roy Pledge <roy.pledge@nxp.com>
> >> ---
> >>   drivers/soc/fsl/Kconfig         |  10 ++
> >>   drivers/soc/fsl/Makefile        |   1 +
> >>   drivers/soc/fsl/dpaa2-console.c | 306
> ++++++++++++++++++++++++++++++++++++++++
> >>   3 files changed, 317 insertions(+)
> >>   create mode 100644 drivers/soc/fsl/dpaa2-console.c
> >>
> >> diff --git a/drivers/soc/fsl/Kconfig b/drivers/soc/fsl/Kconfig index
> >> 61f8e1433d0a..9fe8222c3968 100644
> >> --- a/drivers/soc/fsl/Kconfig
> >> +++ b/drivers/soc/fsl/Kconfig
> >> @@ -29,4 +29,14 @@ config FSL_MC_DPIO
> >>            other DPAA2 objects. This driver does not expose the DPIO
> >>            objects individually, but groups them under a service layer
> >>            API.
> >> +
> >> +config DPAA2_CONSOLE
> >> +       tristate "QorIQ DPAA2 console driver"
> >> +       depends on OF && (ARCH_LAYERSCAPE || (COMPILE_TEST && (ARM
> ||
> >> +ARM64 || X86_LOCAL_APIC || PPC)))
> >
> > I don't know why FSL_MC driver added there architectures dependency
> > for COMPILE_TEST, but is this driver also only buildable on these
> > architectures?  Can we really just remove these dependencies?
> >
> 
> The initial reasoning behind the dependency on the COMPILE_TEST config
> was to catch early build problems on any build configuration.
> And yes, the dpaa2-console can be compiled without a problem on these
> architectures.
> 
> In this case, I would suggest to leave the dependencies as they are but if you
> want I can also remove them.

Can we keep the COMPILE_TEST and remove the (ARM || ARM64 || X86_LOCAL_APIC || PPC) if we are not using any architecture specific stuff?

> 
> >> +       default y
> >> +       help
> >> +         Console driver for DPAA2 platforms. Exports 2 char devices,
> >> +         /dev/dpaa2_mc_console and /dev/dpaa2_aiop_console,
> >> +         which can be used to dump the Management Complex and AIOP
> >> +         firmware logs.
> >>   endmenu
> >> diff --git a/drivers/soc/fsl/Makefile b/drivers/soc/fsl/Makefile
> >> index 803ef1bfb5ff..57762c9fc7da 100644
> >> --- a/drivers/soc/fsl/Makefile
> >> +++ b/drivers/soc/fsl/Makefile
> >> @@ -7,3 +7,4 @@ obj-$(CONFIG_QUICC_ENGINE)              += qe/
> >>   obj-$(CONFIG_CPM)                      += qe/
> >>   obj-$(CONFIG_FSL_GUTS)                 += guts.o
> >>   obj-$(CONFIG_FSL_MC_DPIO)              += dpio/
> >> +obj-$(CONFIG_DPAA2_CONSOLE)            += dpaa2-console.o
> >> diff --git a/drivers/soc/fsl/dpaa2-console.c
> >> b/drivers/soc/fsl/dpaa2-console.c new file mode 100644 index
> >> 000000000000..21a5e121f87b
> >> --- /dev/null
> >> +++ b/drivers/soc/fsl/dpaa2-console.c
> >> @@ -0,0 +1,306 @@
> >> +// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
> >
> > Probably good to have a one-line description of the driver?
> 
> Will add one in the next version.
> 
> >
> >> +/* Copyright 2015-2016 Freescale Semiconductor Inc.
> >> + * Copyright 2018 NXP
> >> + */
> >> +
> >> +#define pr_fmt(fmt) "dpaa2-console: " fmt
> >> +
> >> +#include <linux/module.h>
> >> +#include <linux/of_device.h>
> >> +#include <linux/of_address.h>
> >> +#include <linux/miscdevice.h>
> >> +#include <linux/uaccess.h>
> >> +#include <linux/slab.h>
> >> +#include <linux/fs.h>
> >> +#include <linux/io.h>
> >> +
> >> +MODULE_LICENSE("Dual BSD/GPL");
> >> +MODULE_AUTHOR("Roy Pledge <roy.pledge@nxp.com>");
> >> +MODULE_DESCRIPTION("DPAA2 console driver");
> >
> > These normally go to the bottom of a driver.
> 
> Will move them.
> 
> >
> >> +
> >> +/* MC firmware base low/high registers indexes */ #define
> >> +MCFBALR_OFFSET 0 #define MCFBAHR_OFFSET 1
> >> +
> >> +/* Bit masks used to get the most/least significant part of the MC
> >> +base addr */ #define MC_FW_ADDR_MASK_HIGH 0x1FFFF #define
> >> +MC_FW_ADDR_MASK_LOW  0xE0000000
> >> +
> >> +#define MC_BUFFER_OFFSET 0x01000000
> >> +#define MC_BUFFER_SIZE   (1024 * 1024 * 16)
> >> +#define MC_OFFSET_DELTA  MC_BUFFER_OFFSET
> >> +
> >> +#define AIOP_BUFFER_OFFSET 0x06000000
> >> +#define AIOP_BUFFER_SIZE   (1024 * 1024 * 16)
> >> +#define AIOP_OFFSET_DELTA  0
> >> +
> >> +#define LOG_HEADER_FLAG_BUFFER_WRAPAROUND 0x80000000
> #define
> >> +LAST_BYTE(a) ((a) & ~(LOG_HEADER_FLAG_BUFFER_WRAPAROUND))
> >> +
> >> +/* MC and AIOP Magic words */
> >> +#define MAGIC_MC   0x4d430100
> >> +#define MAGIC_AIOP 0x41494F50
> >> +
> >> +struct log_header {
> >> +       __le32 magic_word;
> >> +       char reserved[4];
> >> +       __le32 buf_start;
> >> +       __le32 buf_length;
> >> +       __le32 last_byte;
> >> +};
> >> +
> >> +struct console_data {
> >> +       char *map_addr;
> >> +       struct log_header *hdr;
> >> +       char *start_addr;
> >> +       char *end_addr;
> >> +       char *end_of_data;
> >> +       char *cur_ptr;
> >> +};
> >> +
> >> +struct resource mc_base_addr;
> >> +
> >> +static inline void adjust_end(struct console_data *cd) {
> >> +       u32 last_byte = readl(&cd->hdr->last_byte);
> >> +
> >> +       cd->end_of_data = cd->start_addr + LAST_BYTE(last_byte); }
> >> +
> >> +static u64 get_mc_fw_base_address(void) {
> >> +       u64 mcfwbase = 0ULL;
> >> +       u32 *mcfbaregs;
> >> +
> >> +       mcfbaregs = (u32 *)ioremap(mc_base_addr.start,
> >> +                                  resource_size(&mc_base_addr));
> >> +       if (!mcfbaregs) {
> >> +               pr_err("could not map MC Firmaware Base registers\n");
> >> +               return -EIO;
> >> +       }
> >> +
> >> +       mcfwbase  = readl(mcfbaregs + MCFBAHR_OFFSET) &
> MC_FW_ADDR_MASK_HIGH;
> >> +       mcfwbase <<= 32;
> >> +       mcfwbase |= readl(mcfbaregs + MCFBALR_OFFSET) &
> MC_FW_ADDR_MASK_LOW;
> >> +       iounmap(mcfbaregs);
> >> +
> >> +       pr_debug("MC base address at 0x%016llx\n", mcfwbase);
> >> +       return mcfwbase;
> >> +}
> >> +
> >> +static ssize_t dpaa2_console_size(struct console_data *cd) {
> >> +       ssize_t size;
> >> +
> >> +       if (cd->cur_ptr <= cd->end_of_data)
> >> +               size = cd->end_of_data - cd->cur_ptr;
> >> +       else
> >> +               size = (cd->end_addr - cd->cur_ptr) +
> >> +                       (cd->end_of_data - cd->start_addr);
> >> +
> >> +       return size;
> >> +}
> >> +
> >> +static int dpaa2_generic_console_open(struct inode *node, struct file *fp,
> >> +                                     u64 offset, u64 size,
> >> +                                     u32 expected_magic,
> >> +                                     u32 offset_delta) {
> >> +       u32 read_magic, wrapped, last_byte, buf_start, buf_length;
> >> +       struct console_data *cd;
> >> +       u64 base_addr;
> >> +       int err;
> >> +
> >> +       cd = kmalloc(sizeof(*cd), GFP_KERNEL);
> >> +       if (!cd)
> >> +               return -ENOMEM;
> >> +
> >> +       base_addr = get_mc_fw_base_address();
> >> +       if (base_addr < 0)
> >
> > We are leaking cd structure here.
> 
> Ugh, that's right. Will fix.
> 
> >
> >> +               return -EIO;
> >> +
> >> +       cd->map_addr = ioremap(base_addr + offset, size);
> >> +       if (!cd->map_addr) {
> >> +               pr_err("cannot map console log memory\n");
> >> +               err = -EIO;
> >> +               goto err_ioremap;
> >> +       }
> >> +
> >> +       cd->hdr = (struct log_header *)cd->map_addr;
> >> +       read_magic = readl(&cd->hdr->magic_word);
> >> +       last_byte = readl(&cd->hdr->last_byte);
> >> +       buf_start = readl(&cd->hdr->buf_start);
> >> +       buf_length = readl(&cd->hdr->buf_length);
> >> +
> >> +       if (read_magic != expected_magic) {
> >> +               pr_warn("expected = %08x, read = %08x\n",
> >> +                       expected_magic, read_magic);
> >> +               err = -EIO;
> >> +               goto err_magic;
> >> +       }
> >> +
> >> +       cd->start_addr = cd->map_addr + buf_start - offset_delta;
> >> +       cd->end_addr = cd->start_addr + buf_length;
> >> +
> >> +       wrapped = last_byte & LOG_HEADER_FLAG_BUFFER_WRAPAROUND;
> >> +
> >> +       adjust_end(cd);
> >> +       if (wrapped && cd->end_of_data != cd->end_addr)
> >> +               cd->cur_ptr = cd->end_of_data + 1;
> >> +       else
> >> +               cd->cur_ptr = cd->start_addr;
> >> +
> >> +       fp->private_data = cd;
> >> +
> >> +       return 0;
> >> +
> >> +err_magic:
> >> +       iounmap(cd->map_addr);
> >> +
> >> +err_ioremap:
> >> +       kfree(cd);
> >> +
> >> +       return err;
> >> +}
> >> +
> >> +static int dpaa2_mc_console_open(struct inode *node, struct file
> >> +*fp) {
> >> +       return dpaa2_generic_console_open(node, fp,
> >> +                                         MC_BUFFER_OFFSET, MC_BUFFER_SIZE,
> >> +                                         MAGIC_MC, MC_OFFSET_DELTA);
> >> +}
> >> +
> >> +static int dpaa2_aiop_console_open(struct inode *node, struct file
> >> +*fp) {
> >> +       return dpaa2_generic_console_open(node, fp,
> >> +                                         AIOP_BUFFER_OFFSET, AIOP_BUFFER_SIZE,
> >> +                                         MAGIC_AIOP,
> >> +AIOP_OFFSET_DELTA); }
> >> +
> >> +static int dpaa2_console_close(struct inode *node, struct file *fp)
> >> +{
> >> +       struct console_data *cd = fp->private_data;
> >> +
> >> +       iounmap(cd->map_addr);
> >> +       kfree(cd);
> >> +       return 0;
> >> +}
> >> +
> >> +static ssize_t dpaa2_console_read(struct file *fp, char __user *buf,
> >> +                                 size_t count, loff_t *f_pos) {
> >> +       struct console_data *cd = fp->private_data;
> >> +       size_t bytes = dpaa2_console_size(cd);
> >> +       size_t bytes_end = cd->end_addr - cd->cur_ptr;
> >> +       size_t written = 0;
> >> +
> >> +       /* Check if we need to adjust the end of data addr */
> >> +       adjust_end(cd);
> >> +
> >> +       if (cd->end_of_data == cd->cur_ptr)
> >> +               return 0;
> >> +
> >> +       if (count < bytes)
> >> +               bytes = count;
> >> +
> >> +       if (bytes > bytes_end) {
> >> +               if (copy_to_user(buf, cd->cur_ptr, bytes_end))
> >> +                       return -EFAULT;
> >> +               buf += bytes_end;
> >> +               cd->cur_ptr = cd->start_addr;
> >> +               bytes -= bytes_end;
> >> +               written += bytes_end;
> >> +       }
> >> +
> >> +       if (copy_to_user(buf, cd->cur_ptr, bytes))
> >> +               return -EFAULT;
> >> +       cd->cur_ptr += bytes;
> >> +       written += bytes;
> >> +
> >> +       return written;
> >> +}
> >> +
> >> +static const struct file_operations dpaa2_mc_console_fops = {
> >> +       .owner          = THIS_MODULE,
> >> +       .open           = dpaa2_mc_console_open,
> >> +       .release        = dpaa2_console_close,
> >> +       .read           = dpaa2_console_read,
> >> +};
> >> +
> >> +static struct miscdevice dpaa2_mc_console_dev = {
> >> +       .minor = MISC_DYNAMIC_MINOR,
> >> +       .name = "dpaa2_mc_console",
> >> +       .fops = &dpaa2_mc_console_fops };
> >> +
> >> +static const struct file_operations dpaa2_aiop_console_fops = {
> >> +       .owner          = THIS_MODULE,
> >> +       .open           = dpaa2_aiop_console_open,
> >> +       .release        = dpaa2_console_close,
> >> +       .read           = dpaa2_console_read,
> >> +};
> >> +
> >> +static struct miscdevice dpaa2_aiop_console_dev = {
> >> +       .minor = MISC_DYNAMIC_MINOR,
> >> +       .name = "dpaa2_aiop_console",
> >> +       .fops = &dpaa2_aiop_console_fops };
> >> +
> >> +static int dpaa2_console_probe(struct platform_device *pdev) {
> >> +       int error;
> >> +
> >> +       error = of_address_to_resource(pdev->dev.of_node, 0,
> &mc_base_addr);
> >> +       if (error < 0) {
> >> +               pr_err("of_address_to_resource() failed for %pOF with %d\n",
> >> +                      pdev->dev.of_node, error);
> >> +               return error;
> >> +       }
> >> +
> >> +       error = misc_register(&dpaa2_mc_console_dev);
> >> +       if (error) {
> >> +               pr_err("dpaa2-console: cannot register device %s\n",
> >> +                      dpaa2_mc_console_dev.name);
> >
> > The pr_fmt already have the dpaa2-console prefix.
> >
> >> +               goto err_register_mc;
> >> +       }
> >> +
> >> +       error = misc_register(&dpaa2_aiop_console_dev);
> >> +       if (error) {
> >> +               pr_err("dpaa2-console: cannot register device %s\n",
> >> +                      dpaa2_aiop_console_dev.name);
> >
> > The pr_fmt already have the dpaa2-console prefix.
> >
> 
> 
> Yep, will remove the duplicate "dpaa2-console" prefix.
> 
> Thanks for the review,
> Ioana C
> 
> 
> >> +               goto err_register_aiop;
> >> +       }
> >> +
> >> +       return 0;
> >> +
> >> +err_register_aiop:
> >> +       misc_deregister(&dpaa2_mc_console_dev);
> >> +err_register_mc:
> >> +       return error;
> >> +}
> >> +
> >> +static int dpaa2_console_remove(struct platform_device *pdev) {
> >> +       misc_deregister(&dpaa2_mc_console_dev);
> >> +       misc_deregister(&dpaa2_aiop_console_dev);
> >> +
> >> +       return 0;
> >> +}
> >> +
> >> +static const struct of_device_id dpaa2_console_match_table[] = {
> >> +       { .compatible = "fsl,dpaa2-console",},
> >> +       {},
> >> +};
> >> +
> >> +MODULE_DEVICE_TABLE(of, dpaa2_console_match_table);
> >> +
> >> +static struct platform_driver dpaa2_console_driver = {
> >> +       .driver = {
> >> +                  .name = "dpaa2-console",
> >> +                  .pm = NULL,
> >> +                  .of_match_table = dpaa2_console_match_table,
> >> +                  },
> >> +       .probe = dpaa2_console_probe,
> >> +       .remove = dpaa2_console_remove, };
> >> +module_platform_driver(dpaa2_console_driver);
> >> --
> >> 1.9.1
> >>
> >