[PATCH v7 09/15] dmaengine: dw-edma: Improve the linked list and data blocks definition

From: Gustavo Pimentel
Date: Thu Feb 18 2021 - 14:39:38 EST


In the previous implementation, the driver assumed that there existed
only two memory spaces that would equally distribute the amount of
read/write channels.

This might not be the case on some other implementations, therefore this
patch change this requirement so that each write/read channel has
its own linked list and data space well defined, which allows
different sizes and locations.

Signed-off-by: Gustavo Pimentel <gustavo.pimentel@xxxxxxxxxxxx>
---
drivers/dma/dw-edma/dw-edma-core.c | 51 +++++-----
drivers/dma/dw-edma/dw-edma-core.h | 9 +-
drivers/dma/dw-edma/dw-edma-pcie.c | 185 ++++++++++++++++++++++++++-----------
3 files changed, 160 insertions(+), 85 deletions(-)

diff --git a/drivers/dma/dw-edma/dw-edma-core.c b/drivers/dma/dw-edma/dw-edma-core.c
index cc39107..552b5f9 100644
--- a/drivers/dma/dw-edma/dw-edma-core.c
+++ b/drivers/dma/dw-edma/dw-edma-core.c
@@ -81,8 +81,13 @@ static struct dw_edma_chunk *dw_edma_alloc_chunk(struct dw_edma_desc *desc)
* - Even chunks originate CB equal to 1
*/
chunk->cb = !(desc->chunks_alloc % 2);
- chunk->ll_region.paddr = dw->ll_region.paddr + chan->ll_off;
- chunk->ll_region.vaddr = dw->ll_region.vaddr + chan->ll_off;
+ if (chan->dir == EDMA_DIR_WRITE) {
+ chunk->ll_region.paddr = dw->ll_region_wr[chan->id].paddr;
+ chunk->ll_region.vaddr = dw->ll_region_wr[chan->id].vaddr;
+ } else {
+ chunk->ll_region.paddr = dw->ll_region_rd[chan->id].paddr;
+ chunk->ll_region.vaddr = dw->ll_region_rd[chan->id].vaddr;
+ }

if (desc->chunk) {
/* Create and add new element into the linked list */
@@ -691,24 +696,13 @@ static int dw_edma_channel_setup(struct dw_edma_chip *chip, bool write,
struct device *dev = chip->dev;
struct dw_edma *dw = chip->dw;
struct dw_edma_chan *chan;
- size_t ll_chunk, dt_chunk;
struct dw_edma_irq *irq;
struct dma_device *dma;
- u32 i, j, cnt, ch_cnt;
u32 alloc, off_alloc;
+ u32 i, j, cnt;
int err = 0;
u32 pos;

- ch_cnt = dw->wr_ch_cnt + dw->rd_ch_cnt;
- ll_chunk = dw->ll_region.sz;
- dt_chunk = dw->dt_region.sz;
-
- /* Calculate linked list chunk for each channel */
- ll_chunk /= roundup_pow_of_two(ch_cnt);
-
- /* Calculate linked list chunk for each channel */
- dt_chunk /= roundup_pow_of_two(ch_cnt);
-
if (write) {
i = 0;
cnt = dw->wr_ch_cnt;
@@ -740,14 +734,14 @@ static int dw_edma_channel_setup(struct dw_edma_chip *chip, bool write,
chan->request = EDMA_REQ_NONE;
chan->status = EDMA_ST_IDLE;

- chan->ll_off = (ll_chunk * i);
- chan->ll_max = (ll_chunk / EDMA_LL_SZ) - 1;
-
- chan->dt_off = (dt_chunk * i);
+ if (write)
+ chan->ll_max = (dw->ll_region_wr[j].sz / EDMA_LL_SZ);
+ else
+ chan->ll_max = (dw->ll_region_rd[j].sz / EDMA_LL_SZ);
+ chan->ll_max -= 1;

- dev_vdbg(dev, "L. List:\tChannel %s[%u] off=0x%.8lx, max_cnt=%u\n",
- write ? "write" : "read", j,
- chan->ll_off, chan->ll_max);
+ dev_vdbg(dev, "L. List:\tChannel %s[%u] max_cnt=%u\n",
+ write ? "write" : "read", j, chan->ll_max);

if (dw->nr_irqs == 1)
pos = 0;
@@ -772,12 +766,15 @@ static int dw_edma_channel_setup(struct dw_edma_chip *chip, bool write,
chan->vc.desc_free = vchan_free_desc;
vchan_init(&chan->vc, dma);

- dt_region->paddr = dw->dt_region.paddr + chan->dt_off;
- dt_region->vaddr = dw->dt_region.vaddr + chan->dt_off;
- dt_region->sz = dt_chunk;
-
- dev_vdbg(dev, "Data:\tChannel %s[%u] off=0x%.8lx\n",
- write ? "write" : "read", j, chan->dt_off);
+ if (write) {
+ dt_region->paddr = dw->dt_region_wr[j].paddr;
+ dt_region->vaddr = dw->dt_region_wr[j].vaddr;
+ dt_region->sz = dw->dt_region_wr[j].sz;
+ } else {
+ dt_region->paddr = dw->dt_region_rd[j].paddr;
+ dt_region->vaddr = dw->dt_region_rd[j].vaddr;
+ dt_region->sz = dw->dt_region_rd[j].sz;
+ }

dw_edma_v0_core_device_config(chan);
}
diff --git a/drivers/dma/dw-edma/dw-edma-core.h b/drivers/dma/dw-edma/dw-edma-core.h
index 650b1c7..cba5436 100644
--- a/drivers/dma/dw-edma/dw-edma-core.h
+++ b/drivers/dma/dw-edma/dw-edma-core.h
@@ -91,11 +91,8 @@ struct dw_edma_chan {
int id;
enum dw_edma_dir dir;

- off_t ll_off;
u32 ll_max;

- off_t dt_off;
-
struct msi_msg msi;

enum dw_edma_request request;
@@ -126,8 +123,10 @@ struct dw_edma {
u16 rd_ch_cnt;

struct dw_edma_region rg_region; /* Registers */
- struct dw_edma_region ll_region; /* Linked list */
- struct dw_edma_region dt_region; /* Data */
+ struct dw_edma_region ll_region_wr[EDMA_MAX_WR_CH];
+ struct dw_edma_region ll_region_rd[EDMA_MAX_RD_CH];
+ struct dw_edma_region dt_region_wr[EDMA_MAX_WR_CH];
+ struct dw_edma_region dt_region_rd[EDMA_MAX_RD_CH];

struct dw_edma_irq *irq;
int nr_irqs;
diff --git a/drivers/dma/dw-edma/dw-edma-pcie.c b/drivers/dma/dw-edma/dw-edma-pcie.c
index 63c62e1..1055fdb 100644
--- a/drivers/dma/dw-edma/dw-edma-pcie.c
+++ b/drivers/dma/dw-edma/dw-edma-pcie.c
@@ -23,19 +23,28 @@
#define DW_PCIE_VSEC_DMA_WR_CH GENMASK(9, 0)
#define DW_PCIE_VSEC_DMA_RD_CH GENMASK(25, 16)

+#define DW_BLOCK(a, b, c) \
+ { \
+ .bar = a, \
+ .off = b, \
+ .sz = c, \
+ },
+
+struct dw_edma_block {
+ enum pci_barno bar;
+ off_t off;
+ size_t sz;
+};
+
struct dw_edma_pcie_data {
/* eDMA registers location */
- enum pci_barno rg_bar;
- off_t rg_off;
- size_t rg_sz;
+ struct dw_edma_block rg;
/* eDMA memory linked list location */
- enum pci_barno ll_bar;
- off_t ll_off;
- size_t ll_sz;
+ struct dw_edma_block ll_wr[EDMA_MAX_WR_CH];
+ struct dw_edma_block ll_rd[EDMA_MAX_RD_CH];
/* eDMA memory data location */
- enum pci_barno dt_bar;
- off_t dt_off;
- size_t dt_sz;
+ struct dw_edma_block dt_wr[EDMA_MAX_WR_CH];
+ struct dw_edma_block dt_rd[EDMA_MAX_RD_CH];
/* Other */
enum dw_edma_map_format mf;
u8 irqs;
@@ -45,22 +54,40 @@ struct dw_edma_pcie_data {

static const struct dw_edma_pcie_data snps_edda_data = {
/* eDMA registers location */
- .rg_bar = BAR_0,
- .rg_off = 0x00001000, /* 4 Kbytes */
- .rg_sz = 0x00002000, /* 8 Kbytes */
+ .rg.bar = BAR_0,
+ .rg.off = 0x00001000, /* 4 Kbytes */
+ .rg.sz = 0x00002000, /* 8 Kbytes */
/* eDMA memory linked list location */
- .ll_bar = BAR_2,
- .ll_off = 0x00000000, /* 0 Kbytes */
- .ll_sz = 0x00800000, /* 8 Mbytes */
+ .ll_wr = {
+ /* Channel 0 - BAR 2, offset 0 Mbytes, size 2 Mbytes */
+ DW_BLOCK(BAR_2, 0x00000000, 0x00200000)
+ /* Channel 1 - BAR 2, offset 2 Mbytes, size 2 Mbytes */
+ DW_BLOCK(BAR_2, 0x00200000, 0x00200000)
+ },
+ .ll_rd = {
+ /* Channel 0 - BAR 2, offset 4 Mbytes, size 2 Mbytes */
+ DW_BLOCK(BAR_2, 0x00400000, 0x00200000)
+ /* Channel 1 - BAR 2, offset 6 Mbytes, size 2 Mbytes */
+ DW_BLOCK(BAR_2, 0x00600000, 0x00200000)
+ },
/* eDMA memory data location */
- .dt_bar = BAR_2,
- .dt_off = 0x00800000, /* 8 Mbytes */
- .dt_sz = 0x03800000, /* 56 Mbytes */
+ .dt_wr = {
+ /* Channel 0 - BAR 2, offset 8 Mbytes, size 14 Mbytes */
+ DW_BLOCK(BAR_2, 0x00800000, 0x00e00000)
+ /* Channel 1 - BAR 2, offset 22 Mbytes, size 14 Mbytes */
+ DW_BLOCK(BAR_2, 0x01600000, 0x00e00000)
+ },
+ .dt_rd = {
+ /* Channel 0 - BAR 2, offset 36 Mbytes, size 14 Mbytes */
+ DW_BLOCK(BAR_2, 0x02400000, 0x00e00000)
+ /* Channel 1 - BAR 2, offset 50 Mbytes, size 14 Mbytes */
+ DW_BLOCK(BAR_2, 0x03200000, 0x00e00000)
+ },
/* Other */
.mf = EDMA_MF_EDMA_UNROLL,
.irqs = 1,
- .wr_ch_cnt = 0,
- .rd_ch_cnt = 0,
+ .wr_ch_cnt = 2,
+ .rd_ch_cnt = 2,
};

static int dw_edma_pcie_irq_vector(struct device *dev, unsigned int nr)
@@ -98,18 +125,20 @@ static void dw_edma_pcie_get_vsec_dma_data(struct pci_dev *pdev,
return;

pdata->mf = map;
- pdata->rg_bar = FIELD_GET(DW_PCIE_VSEC_DMA_BAR, val);
+ pdata->rg.bar = FIELD_GET(DW_PCIE_VSEC_DMA_BAR, val);

pci_read_config_dword(pdev, vsec + 0xc, &val);
- pdata->wr_ch_cnt = FIELD_GET(DW_PCIE_VSEC_DMA_WR_CH, val);
- pdata->rd_ch_cnt = FIELD_GET(DW_PCIE_VSEC_DMA_RD_CH, val);
+ pdata->wr_ch_cnt = min_t(u16, pdata->wr_ch_cnt,
+ FIELD_GET(DW_PCIE_VSEC_DMA_WR_CH, val));
+ pdata->rd_ch_cnt = min_t(u16, pdata->rd_ch_cnt,
+ FIELD_GET(DW_PCIE_VSEC_DMA_RD_CH, val));

pci_read_config_dword(pdev, vsec + 0x14, &val);
off = val;
pci_read_config_dword(pdev, vsec + 0x10, &val);
off <<= 32;
off |= val;
- pdata->rg_off = off;
+ pdata->rg.off = off;
}

static int dw_edma_pcie_probe(struct pci_dev *pdev,
@@ -121,6 +150,7 @@ static int dw_edma_pcie_probe(struct pci_dev *pdev,
struct dw_edma_chip *chip;
struct dw_edma *dw;
int err, nr_irqs;
+ int i, mask;

/* Enable PCI device */
err = pcim_enable_device(pdev);
@@ -138,10 +168,16 @@ static int dw_edma_pcie_probe(struct pci_dev *pdev,
dw_edma_pcie_get_vsec_dma_data(pdev, &vsec_data);

/* Mapping PCI BAR regions */
- err = pcim_iomap_regions(pdev, BIT(vsec_data.rg_bar) |
- BIT(vsec_data.ll_bar) |
- BIT(vsec_data.dt_bar),
- pci_name(pdev));
+ mask = BIT(vsec_data.rg.bar);
+ for (i = 0; i < vsec_data.wr_ch_cnt; i++) {
+ mask |= BIT(vsec_data.ll_wr[i].bar);
+ mask |= BIT(vsec_data.dt_wr[i].bar);
+ }
+ for (i = 0; i < vsec_data.rd_ch_cnt; i++) {
+ mask |= BIT(vsec_data.ll_rd[i].bar);
+ mask |= BIT(vsec_data.dt_rd[i].bar);
+ }
+ err = pcim_iomap_regions(pdev, mask, pci_name(pdev));
if (err) {
pci_err(pdev, "eDMA BAR I/O remapping failed\n");
return err;
@@ -197,30 +233,56 @@ static int dw_edma_pcie_probe(struct pci_dev *pdev,
chip->id = pdev->devfn;
chip->irq = pdev->irq;

- dw->rg_region.vaddr = pcim_iomap_table(pdev)[vsec_data.rg_bar];
- dw->rg_region.vaddr += vsec_data.rg_off;
- dw->rg_region.paddr = pdev->resource[vsec_data.rg_bar].start;
- dw->rg_region.paddr += vsec_data.rg_off;
- dw->rg_region.sz = vsec_data.rg_sz;
-
- dw->ll_region.vaddr = pcim_iomap_table(pdev)[vsec_data.ll_bar];
- dw->ll_region.vaddr += vsec_data.ll_off;
- dw->ll_region.paddr = pdev->resource[vsec_data.ll_bar].start;
- dw->ll_region.paddr += vsec_data.ll_off;
- dw->ll_region.sz = vsec_data.ll_sz;
-
- dw->dt_region.vaddr = pcim_iomap_table(pdev)[vsec_data.dt_bar];
- dw->dt_region.vaddr += vsec_data.dt_off;
- dw->dt_region.paddr = pdev->resource[vsec_data.dt_bar].start;
- dw->dt_region.paddr += vsec_data.dt_off;
- dw->dt_region.sz = vsec_data.dt_sz;
-
dw->mf = vsec_data.mf;
dw->nr_irqs = nr_irqs;
dw->ops = &dw_edma_pcie_core_ops;
dw->wr_ch_cnt = vsec_data.wr_ch_cnt;
dw->rd_ch_cnt = vsec_data.rd_ch_cnt;

+ dw->rg_region.vaddr = pcim_iomap_table(pdev)[vsec_data.rg.bar];
+ dw->rg_region.vaddr += vsec_data.rg.off;
+ dw->rg_region.paddr = pdev->resource[vsec_data.rg.bar].start;
+ dw->rg_region.paddr += vsec_data.rg.off;
+ dw->rg_region.sz = vsec_data.rg.sz;
+
+ for (i = 0; i < dw->wr_ch_cnt; i++) {
+ struct dw_edma_region *ll_region = &dw->ll_region_wr[i];
+ struct dw_edma_region *dt_region = &dw->dt_region_wr[i];
+ struct dw_edma_block *ll_block = &vsec_data.ll_wr[i];
+ struct dw_edma_block *dt_block = &vsec_data.dt_wr[i];
+
+ ll_region->vaddr = pcim_iomap_table(pdev)[ll_block->bar];
+ ll_region->vaddr += ll_block->off;
+ ll_region->paddr = pdev->resource[ll_block->bar].start;
+ ll_region->paddr += ll_block->off;
+ ll_region->sz = ll_block->sz;
+
+ dt_region->vaddr = pcim_iomap_table(pdev)[dt_block->bar];
+ dt_region->vaddr += dt_block->off;
+ dt_region->paddr = pdev->resource[dt_block->bar].start;
+ dt_region->paddr += dt_block->off;
+ dt_region->sz = dt_block->sz;
+ }
+
+ for (i = 0; i < dw->rd_ch_cnt; i++) {
+ struct dw_edma_region *ll_region = &dw->ll_region_rd[i];
+ struct dw_edma_region *dt_region = &dw->dt_region_rd[i];
+ struct dw_edma_block *ll_block = &vsec_data.ll_rd[i];
+ struct dw_edma_block *dt_block = &vsec_data.dt_rd[i];
+
+ ll_region->vaddr = pcim_iomap_table(pdev)[ll_block->bar];
+ ll_region->vaddr += ll_block->off;
+ ll_region->paddr = pdev->resource[ll_block->bar].start;
+ ll_region->paddr += ll_block->off;
+ ll_region->sz = ll_block->sz;
+
+ dt_region->vaddr = pcim_iomap_table(pdev)[dt_block->bar];
+ dt_region->vaddr += dt_block->off;
+ dt_region->paddr = pdev->resource[dt_block->bar].start;
+ dt_region->paddr += dt_block->off;
+ dt_region->sz = dt_block->sz;
+ }
+
/* Debug info */
if (dw->mf == EDMA_MF_EDMA_LEGACY)
pci_dbg(pdev, "Version:\teDMA Port Logic (0x%x)\n", dw->mf);
@@ -232,16 +294,33 @@ static int dw_edma_pcie_probe(struct pci_dev *pdev,
pci_dbg(pdev, "Version:\tUnknown (0x%x)\n", dw->mf);

pci_dbg(pdev, "Registers:\tBAR=%u, off=0x%.8lx, sz=0x%zx bytes, addr(v=%p, p=%pa)\n",
- vsec_data.rg_bar, vsec_data.rg_off, vsec_data.rg_sz,
+ vsec_data.rg.bar, vsec_data.rg.off, vsec_data.rg.sz,
dw->rg_region.vaddr, &dw->rg_region.paddr);

- pci_dbg(pdev, "L. List:\tBAR=%u, off=0x%.8lx, sz=0x%zx bytes, addr(v=%p, p=%pa)\n",
- vsec_data.ll_bar, vsec_data.ll_off, vsec_data.ll_sz,
- dw->ll_region.vaddr, &dw->ll_region.paddr);

- pci_dbg(pdev, "Data:\tBAR=%u, off=0x%.8lx, sz=0x%zx bytes, addr(v=%p, p=%pa)\n",
- vsec_data.dt_bar, vsec_data.dt_off, vsec_data.dt_sz,
- dw->dt_region.vaddr, &dw->dt_region.paddr);
+ for (i = 0; i < dw->wr_ch_cnt; i++) {
+ pci_dbg(pdev, "L. List:\tWRITE CH%.2u, BAR=%u, off=0x%.8lx, sz=0x%zx bytes, addr(v=%p, p=%pa)\n",
+ i, vsec_data.ll_wr[i].bar,
+ vsec_data.ll_wr[i].off, dw->ll_region_wr[i].sz,
+ dw->ll_region_wr[i].vaddr, &dw->ll_region_wr[i].paddr);
+
+ pci_dbg(pdev, "Data:\tWRITE CH%.2u, BAR=%u, off=0x%.8lx, sz=0x%zx bytes, addr(v=%p, p=%pa)\n",
+ i, vsec_data.dt_wr[i].bar,
+ vsec_data.dt_wr[i].off, dw->dt_region_wr[i].sz,
+ dw->dt_region_wr[i].vaddr, &dw->dt_region_wr[i].paddr);
+ }
+
+ for (i = 0; i < dw->rd_ch_cnt; i++) {
+ pci_dbg(pdev, "L. List:\tREAD CH%.2u, BAR=%u, off=0x%.8lx, sz=0x%zx bytes, addr(v=%p, p=%pa)\n",
+ i, vsec_data.ll_rd[i].bar,
+ vsec_data.ll_rd[i].off, dw->ll_region_rd[i].sz,
+ dw->ll_region_rd[i].vaddr, &dw->ll_region_rd[i].paddr);
+
+ pci_dbg(pdev, "Data:\tREAD CH%.2u, BAR=%u, off=0x%.8lx, sz=0x%zx bytes, addr(v=%p, p=%pa)\n",
+ i, vsec_data.dt_rd[i].bar,
+ vsec_data.dt_rd[i].off, dw->dt_region_rd[i].sz,
+ dw->dt_region_rd[i].vaddr, &dw->dt_region_rd[i].paddr);
+ }

pci_dbg(pdev, "Nr. IRQs:\t%u\n", dw->nr_irqs);

--
2.7.4