Re: [PATCH v2 19/27] coresight: catu: Plug in CATU as a backend for ETR buffer
From: Mathieu Poirier
Date: Mon May 07 2018 - 18:03:02 EST
On Tue, May 01, 2018 at 10:10:49AM +0100, Suzuki K Poulose wrote:
> Now that we can use a CATU with a scatter gather table, add support
> for the TMC ETR to make use of the connected CATU in translate mode.
> This is done by adding CATU as new buffer mode. CATU's SLADDR must
> always be 4K aligned. Thus the INADDR (base VA) is always 1M aligned
> and we adjust the DBA for the ETR to align to the "offset" within
> the 1MB page.
>
> Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
> Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
> ---
> drivers/hwtracing/coresight/coresight-catu.c | 189 +++++++++++++++++++++++-
> drivers/hwtracing/coresight/coresight-catu.h | 30 ++++
> drivers/hwtracing/coresight/coresight-tmc-etr.c | 23 ++-
> drivers/hwtracing/coresight/coresight-tmc.h | 1 +
> 4 files changed, 235 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/hwtracing/coresight/coresight-catu.c b/drivers/hwtracing/coresight/coresight-catu.c
> index 4cc2928..a4792fa 100644
> --- a/drivers/hwtracing/coresight/coresight-catu.c
> +++ b/drivers/hwtracing/coresight/coresight-catu.c
> @@ -22,6 +22,21 @@
> dev_get_drvdata(csdev->dev.parent)
>
> /*
> + * catu_etr_buf - CATU buffer descriptor
> + * @catu_table - SG table for the CATU
> + * @sladdr - Table base address for CATU
> + * @start_offset - Current offset where the ETR starts writing
> + * within the buffer.
> + * @cur_size - Current size used by the ETR.
> + */
> +struct catu_etr_buf {
> + struct tmc_sg_table *catu_table;
> + u64 sladdr;
> + u64 start_offset;
> + u64 cur_size;
> +};
> +
> +/*
> * CATU uses a page size of 4KB for page tables as well as data pages.
> * Each 64bit entry in the table has the following format.
> *
> @@ -87,6 +102,9 @@ typedef u64 cate_t;
> (((cate_t)(addr) & CATU_ADDR_MASK) | CATU_ENTRY_VALID)
> #define CATU_ENTRY_ADDR(entry) ((cate_t)(entry) & ~((cate_t)CATU_ENTRY_VALID))
>
> +/* CATU expects the INADDR to be aligned to 1M. */
> +#define CATU_DEFAULT_INADDR (1ULL << 20)
> +
> /*
> * Index into the CATU entry pointing to the page within
> * the table. Each table entry can point to a 4KB page, with
> @@ -401,7 +419,7 @@ catu_populate_table(struct tmc_sg_table *catu_table)
> }
> }
>
> -static struct tmc_sg_table __maybe_unused *
> +static struct tmc_sg_table *
> catu_init_sg_table(struct device *catu_dev, int node,
> ssize_t size, void **pages)
> {
> @@ -429,6 +447,149 @@ catu_init_sg_table(struct device *catu_dev, int node,
> return catu_table;
> }
>
> +static void catu_free_etr_buf(struct etr_buf *etr_buf)
> +{
> + struct catu_etr_buf *catu_buf;
> +
> + if (!etr_buf || etr_buf->mode != ETR_MODE_CATU || !etr_buf->private)
> + return;
> + catu_buf = etr_buf->private;
> + tmc_free_sg_table(catu_buf->catu_table);
> + kfree(catu_buf);
> +}
> +
> +static ssize_t catu_get_data_etr_buf(struct etr_buf *etr_buf, u64 offset,
> + size_t len, char **bufpp)
> +{
> + struct catu_etr_buf *catu_buf = etr_buf->private;
> +
> + return tmc_sg_table_get_data(catu_buf->catu_table, offset, len, bufpp);
> +}
> +
> +static void catu_sync_etr_buf(struct etr_buf *etr_buf, u64 rrp, u64 rwp)
> +{
> + struct catu_etr_buf *catu_buf = etr_buf->private;
> + s64 r_offset, w_offset;
> + unsigned long buf_size = tmc_sg_table_buf_size(catu_buf->catu_table);
> +
> + /*
> + * ETR started off at etr_buf->hwaddr which corresponds to
> + * start_offset within the trace buffer. Convert the RRP/RWP
> + * offsets within the trace buffer.
> + */
> + r_offset = (s64)rrp - etr_buf->hwaddr + catu_buf->start_offset;
> + r_offset -= (r_offset > buf_size) ? buf_size : 0;
> +
> + w_offset = (s64)rwp - etr_buf->hwaddr + catu_buf->start_offset;
> + w_offset -= (w_offset > buf_size) ? buf_size : 0;
> +
> + if (!etr_buf->full) {
> + etr_buf->len = w_offset - r_offset;
> + if (w_offset < r_offset)
> + etr_buf->len += buf_size;
> + } else {
> + etr_buf->len = etr_buf->size;
> + }
> +
> + etr_buf->offset = r_offset;
> + tmc_sg_table_sync_data_range(catu_buf->catu_table,
> + r_offset, etr_buf->len);
> +}
> +
> +static inline void catu_set_etr_buf(struct etr_buf *etr_buf, u64 base, u64 size)
> +{
> + struct catu_etr_buf *catu_buf = etr_buf->private;
> +
> + catu_buf->start_offset = base;
> + catu_buf->cur_size = size;
> +
> + /*
> + * CATU always maps 1MB aligned addresses. ETR should start at
> + * the offset within the first table.
> + */
> + etr_buf->hwaddr = CATU_DEFAULT_INADDR + (base & (SZ_1M - 1));
> + etr_buf->size = size;
> + etr_buf->rwp = etr_buf->rrp = etr_buf->hwaddr;
> +}
> +
> +static int catu_restore_etr_buf(struct etr_buf *etr_buf,
> + unsigned long r_offset,
> + unsigned long w_offset,
> + unsigned long size,
> + u32 status,
> + bool has_save_restore)
> +{
> + struct catu_etr_buf *catu_buf = etr_buf->private;
> + u64 end = w_offset + size;
> + u64 cur_end = catu_buf->start_offset + catu_buf->cur_size;
> +
> + /*
> + * We cannot support rotation without a full table
> + * at the end. i.e, the buffer size should be aligned
> + * to 1MB.
> + */
> + if (tmc_sg_table_buf_size(catu_buf->catu_table) & (SZ_1M - 1))
> + return -EINVAL;
> +
> + /*
> + * We don't have to make any changes to the table if the
> + * current (start, end) and the new (start, end) are in the
> + * same pages respectively.
> + */
> + if ((w_offset ^ catu_buf->start_offset) & ~(CATU_PAGE_SIZE - 1) ||
> + (end ^ cur_end) & ~(CATU_PAGE_SIZE - 1)) {
> + catu_reset_table(catu_buf->catu_table, catu_buf->start_offset,
> + catu_buf->cur_size);
> + catu_buf->sladdr = catu_set_table(catu_buf->catu_table,
> + w_offset, size);
> + }
> +
> + catu_set_etr_buf(etr_buf, w_offset, size);
> +
> + return 0;
> +}
> +
> +static int catu_alloc_etr_buf(struct tmc_drvdata *tmc_drvdata,
> + struct etr_buf *etr_buf, int node, void **pages)
> +{
> + struct coresight_device *csdev;
> + struct device *catu_dev;
> + struct tmc_sg_table *catu_table;
> + struct catu_etr_buf *catu_buf;
> +
> + csdev = tmc_etr_get_catu_device(tmc_drvdata);
> + if (!csdev)
> + return -ENODEV;
> + catu_dev = csdev->dev.parent;
> + catu_buf = kzalloc(sizeof(*catu_buf), GFP_KERNEL);
> + if (!catu_buf)
> + return -ENOMEM;
> +
> + catu_table = catu_init_sg_table(catu_dev, node, etr_buf->size, pages);
> + if (IS_ERR(catu_table)) {
> + kfree(catu_buf);
> + return PTR_ERR(catu_table);
> + }
> +
> + etr_buf->mode = ETR_MODE_CATU;
> + etr_buf->private = catu_buf;
> + catu_buf->catu_table = catu_table;
> +
> + /* By default make the buffer linear from 0 with full size */
> + catu_set_etr_buf(etr_buf, 0, etr_buf->size);
> + catu_dump_table(catu_table);
> +
> + return 0;
> +}
> +
> +const struct etr_buf_operations etr_catu_buf_ops = {
> + .alloc = catu_alloc_etr_buf,
> + .free = catu_free_etr_buf,
> + .sync = catu_sync_etr_buf,
> + .get_data = catu_get_data_etr_buf,
> + .restore = catu_restore_etr_buf,
> +};
> +
> coresight_simple_reg32(struct catu_drvdata, control, CATU_CONTROL);
> coresight_simple_reg32(struct catu_drvdata, status, CATU_STATUS);
> coresight_simple_reg32(struct catu_drvdata, mode, CATU_MODE);
> @@ -467,9 +628,11 @@ static inline int catu_wait_for_ready(struct catu_drvdata *drvdata)
> CATU_STATUS, CATU_STATUS_READY, 1);
> }
>
> -static int catu_enable_hw(struct catu_drvdata *drvdata, void *__unused)
> +static int catu_enable_hw(struct catu_drvdata *drvdata, void *data)
> {
> u32 control;
> + u32 mode;
> + struct etr_buf *etr_buf = data;
>
> if (catu_wait_for_ready(drvdata))
> dev_warn(drvdata->dev, "Timeout while waiting for READY\n");
> @@ -481,9 +644,27 @@ static int catu_enable_hw(struct catu_drvdata *drvdata, void *__unused)
> }
>
> control |= BIT(CATU_CONTROL_ENABLE);
> - catu_write_mode(drvdata, CATU_MODE_PASS_THROUGH);
> +
> + if (etr_buf && etr_buf->mode == ETR_MODE_CATU) {
> + struct catu_etr_buf *catu_buf = etr_buf->private;
> +
> + mode = CATU_MODE_TRANSLATE;
> + catu_write_axictrl(drvdata, CATU_OS_AXICTRL);
> + catu_write_sladdr(drvdata, catu_buf->sladdr);
> + catu_write_inaddr(drvdata, CATU_DEFAULT_INADDR);
> + } else {
> + mode = CATU_MODE_PASS_THROUGH;
> + catu_write_sladdr(drvdata, 0);
> + catu_write_inaddr(drvdata, 0);
> + }
> +
> + catu_write_irqen(drvdata, 0);
> + catu_write_mode(drvdata, mode);
> catu_write_control(drvdata, control);
> - dev_dbg(drvdata->dev, "Enabled in Pass through mode\n");
> + dev_dbg(drvdata->dev, "Enabled in %s mode\n",
> + (mode == CATU_MODE_PASS_THROUGH) ?
> + "Pass through" :
> + "Translate");
> return 0;
> }
>
> diff --git a/drivers/hwtracing/coresight/coresight-catu.h b/drivers/hwtracing/coresight/coresight-catu.h
> index cd58d6f..b673a73 100644
> --- a/drivers/hwtracing/coresight/coresight-catu.h
> +++ b/drivers/hwtracing/coresight/coresight-catu.h
> @@ -29,6 +29,32 @@
> #define CATU_MODE_PASS_THROUGH 0U
> #define CATU_MODE_TRANSLATE 1U
>
> +#define CATU_AXICTRL_ARCACHE_SHIFT 4
> +#define CATU_AXICTRL_ARCACHE_MASK 0xf
> +#define CATU_AXICTRL_ARPROT_MASK 0x3
> +#define CATU_AXICTRL_ARCACHE(arcache) \
> + (((arcache) & CATU_AXICTRL_ARCACHE_MASK) << CATU_AXICTRL_ARCACHE_SHIFT)
> +
> +#define CATU_AXICTRL_VAL(arcache, arprot) \
> + (CATU_AXICTRL_ARCACHE(arcache) | ((arprot) & CATU_AXICTRL_ARPROT_MASK))
> +
> +#define AXI3_AxCACHE_WB_READ_ALLOC 0x7
> +/*
> + * AXI - ARPROT bits:
> + * See AMBA AXI & ACE Protocol specification (ARM IHI 0022E)
> + * sectionA4.7 Access Permissions.
> + *
> + * Bit 0: 0 - Unprivileged access, 1 - Privileged access
> + * Bit 1: 0 - Secure access, 1 - Non-secure access.
> + * Bit 2: 0 - Data access, 1 - instruction access.
> + *
> + * CATU AXICTRL:ARPROT[2] is res0 as we always access data.
> + */
> +#define CATU_OS_ARPROT 0x2
> +
> +#define CATU_OS_AXICTRL \
> + CATU_AXICTRL_VAL(AXI3_AxCACHE_WB_READ_ALLOC, CATU_OS_ARPROT)
> +
> #define CATU_STATUS_READY 8
> #define CATU_STATUS_ADRERR 0
> #define CATU_STATUS_AXIERR 4
> @@ -71,6 +97,8 @@ catu_write_##name(struct catu_drvdata *drvdata, u64 val) \
>
> CATU_REG32(control, CATU_CONTROL);
> CATU_REG32(mode, CATU_MODE);
> +CATU_REG32(irqen, CATU_IRQEN);
> +CATU_REG32(axictrl, CATU_AXICTRL);
> CATU_REG_PAIR(sladdr, CATU_SLADDRLO, CATU_SLADDRHI)
> CATU_REG_PAIR(inaddr, CATU_INADDRLO, CATU_INADDRHI)
>
> @@ -86,4 +114,6 @@ static inline bool coresight_is_catu_device(struct coresight_device *csdev)
> subtype == CORESIGHT_DEV_SUBTYPE_HELPER_CATU;
> }
>
> +extern const struct etr_buf_operations etr_catu_buf_ops;
> +
> #endif
> diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
> index 25e7feb..41dde0a 100644
> --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
> +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
> @@ -941,6 +941,9 @@ static const struct etr_buf_operations etr_sg_buf_ops = {
> static const struct etr_buf_operations *etr_buf_ops[] = {
> [ETR_MODE_FLAT] = &etr_flat_buf_ops,
> [ETR_MODE_ETR_SG] = &etr_sg_buf_ops,
> +#ifdef CONFIG_CORESIGHT_CATU
> + [ETR_MODE_CATU] = &etr_catu_buf_ops,
> +#endif
> };
>
> static inline int tmc_etr_mode_alloc_buf(int mode,
> @@ -953,6 +956,9 @@ static inline int tmc_etr_mode_alloc_buf(int mode,
> switch (mode) {
> case ETR_MODE_FLAT:
> case ETR_MODE_ETR_SG:
> +#ifdef CONFIG_CORESIGHT_CATU
> + case ETR_MODE_CATU:
> +#endif
I really wish we could avoid doing something like this (and the above) but every
alternate solution I come up with is either uglier or on par with it...
Unless someone comes up with a bright idea we'll simply have to let it be.
While looking for a solution I noticed that tmc_etr_get_catu_device()
could be moved to coresight-catu.h. That way we wouldn't have to include
coresight-catu.h every time coresight-tmc.h is present in a file.
> rc = etr_buf_ops[mode]->alloc(drvdata, etr_buf, node, pages);
> if (!rc)
> etr_buf->ops = etr_buf_ops[mode];
> @@ -977,11 +983,15 @@ static struct etr_buf *tmc_alloc_etr_buf(struct tmc_drvdata *drvdata,
> int rc = -ENOMEM;
> bool has_etr_sg, has_iommu;
> bool has_flat, has_save_restore;
> + bool has_sg, has_catu;
> struct etr_buf *etr_buf;
>
> has_etr_sg = tmc_etr_has_cap(drvdata, TMC_ETR_SG);
> has_iommu = iommu_get_domain_for_dev(drvdata->dev);
> has_save_restore = tmc_etr_has_cap(drvdata, TMC_ETR_SAVE_RESTORE);
> + has_catu = !!tmc_etr_get_catu_device(drvdata);
> +
> + has_sg = has_catu || has_etr_sg;
>
> /*
> * We can normally use flat DMA buffer provided that the buffer
> @@ -1006,7 +1016,7 @@ static struct etr_buf *tmc_alloc_etr_buf(struct tmc_drvdata *drvdata,
> if ((flags & ETR_BUF_F_RESTORE_STATUS) && !has_save_restore)
> return ERR_PTR(-EINVAL);
>
> - if (!has_flat && !has_etr_sg) {
> + if (!has_flat && !has_sg) {
> dev_dbg(drvdata->dev,
> "No available backends for ETR buffer with flags %x\n",
> flags);
> @@ -1032,17 +1042,22 @@ static struct etr_buf *tmc_alloc_etr_buf(struct tmc_drvdata *drvdata,
> *
> */
> if (!pages && has_flat &&
> - (!has_etr_sg || has_iommu || size < SZ_1M))
> + (!has_sg || has_iommu || size < SZ_1M))
> rc = tmc_etr_mode_alloc_buf(ETR_MODE_FLAT, drvdata,
> etr_buf, node, pages);
> if (rc && has_etr_sg)
> rc = tmc_etr_mode_alloc_buf(ETR_MODE_ETR_SG, drvdata,
> etr_buf, node, pages);
> + if (rc && has_catu)
> + rc = tmc_etr_mode_alloc_buf(ETR_MODE_CATU, drvdata,
> + etr_buf, node, pages);
> if (rc) {
> kfree(etr_buf);
> return ERR_PTR(rc);
> }
>
> + dev_dbg(drvdata->dev, "allocated buffer of size %ldKB in mode %d\n",
> + (unsigned long)size >> 10, etr_buf->mode);
> return etr_buf;
> }
>
> @@ -1136,7 +1151,7 @@ static inline void tmc_etr_enable_catu(struct tmc_drvdata *drvdata)
> struct coresight_device *catu = tmc_etr_get_catu_device(drvdata);
>
> if (catu && helper_ops(catu)->enable)
> - helper_ops(catu)->enable(catu, NULL);
> + helper_ops(catu)->enable(catu, drvdata->etr_buf);
> }
>
> static inline void tmc_etr_disable_catu(struct tmc_drvdata *drvdata)
> @@ -1144,7 +1159,7 @@ static inline void tmc_etr_disable_catu(struct tmc_drvdata *drvdata)
> struct coresight_device *catu = tmc_etr_get_catu_device(drvdata);
>
> if (catu && helper_ops(catu)->disable)
> - helper_ops(catu)->disable(catu, NULL);
> + helper_ops(catu)->disable(catu, drvdata->etr_buf);
> }
>
> static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
> diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h
> index 1bdfb38..1f6aa49 100644
> --- a/drivers/hwtracing/coresight/coresight-tmc.h
> +++ b/drivers/hwtracing/coresight/coresight-tmc.h
> @@ -139,6 +139,7 @@ enum tmc_mem_intf_width {
> enum etr_mode {
> ETR_MODE_FLAT, /* Uses contiguous flat buffer */
> ETR_MODE_ETR_SG, /* Uses in-built TMC ETR SG mechanism */
> + ETR_MODE_CATU, /* Use SG mechanism in CATU */
> };
>
> /* ETR buffer should support save-restore */
> --
> 2.7.4
>