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soc: ti: pruss: Add support for PRU-ICSSs on AM437x SoCs

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The AM437x SoCs have two different PRU-ICSS subsystems: PRU-ICSS1
and a smaller PRU-ICSS0. Enhance the PRUSS platform driver to support
both the PRU-ICSS sub-systems on these SoCs.

The PRU-ICSS1 on AM437x is very similar to the PRU-ICSS on AM33xx
except for few minor differences - increased Instruction RAM, increased
Shared Data RAM2, and 1 less interrupt (PRUSS host interrupt 7 which is
redirected to the other PRUSS) towards the MPU INTC. The PRU-ICSS0 is
a cut-down version of the IP, with less DRAM per PRU, no Shared DRAM etc.
It also does not have direct access to L3 bus regions, there is a single
interface to L3 for both PRUSS0 and PRUSS1, and it would have to go
through the PRUSS1's interface. The PRUSS_SYSCFG register is reserved on
PRUSS0, so any external access requires the programming the corresponding
PRUSS_SYSCFG register in PRUSS1. It does have its own dedicated I/O lines
though. Note that this instance does not support any PRU Ethernet related
use cases.

The adaptation uses SoC-specific compatibles in the driver and uses
a newly introduced pruss_match_private_data structure and the
pruss_get_private_data() function to retrieve a PRUSS instance specific
data using a device-name based lookup logic. The reset and the L3 external
access are managed by the parent interconnect ti-sysc bus driver so that
PRUSS1 and PRUSS0 can be independently supported.

Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
This commit is contained in:
Suman Anna 2020-09-11 21:43:35 -07:00 committed by Santosh Shilimkar
parent dc1129564a
commit 78251639d3
2 changed files with 35 additions and 2 deletions
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2
drivers/soc/ti/Kconfig
View File

@ -103,7 +103,7 @@ config TI_K3_SOCINFO
config TI_PRUSS
tristate "TI PRU-ICSS Subsystem Platform drivers"
depends on SOC_AM33XX
depends on SOC_AM33XX || SOC_AM43XX
select MFD_SYSCON
help
TI PRU-ICSS Subsystem platform specific support.

35
drivers/soc/ti/pruss.c
View File

@ -17,6 +17,14 @@
#include <linux/pm_runtime.h>
#include <linux/pruss_driver.h>
/**
* struct pruss_private_data - PRUSS driver private data
* @has_no_sharedram: flag to indicate the absence of PRUSS Shared Data RAM
*/
struct pruss_private_data {
bool has_no_sharedram;
};
static int pruss_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
@ -25,8 +33,15 @@ static int pruss_probe(struct platform_device *pdev)
struct pruss *pruss;
struct resource res;
int ret, i, index;
const struct pruss_private_data *data;
const char *mem_names[PRUSS_MEM_MAX] = { "dram0", "dram1", "shrdram2" };
data = of_device_get_match_data(&pdev->dev);
if (IS_ERR(data)) {
dev_err(dev, "missing private data\n");
return -ENODEV;
}
ret = dma_set_coherent_mask(dev, DMA_BIT_MASK(32));
if (ret) {
dev_err(dev, "failed to set the DMA coherent mask");
@ -45,7 +60,14 @@ static int pruss_probe(struct platform_device *pdev)
return -ENODEV;
}
for (i = 0; i < ARRAY_SIZE(mem_names); i++) {
for (i = 0; i < PRUSS_MEM_MAX; i++) {
/*
* On AM437x one of two PRUSS units don't contain Shared RAM,
* skip it
*/
if (data && data->has_no_sharedram && i == PRUSS_MEM_SHRD_RAM2)
continue;
index = of_property_match_string(child, "reg-names",
mem_names[i]);
if (index < 0) {
@ -126,8 +148,19 @@ static int pruss_remove(struct platform_device *pdev)
return 0;
}
/* instance-specific driver private data */
static const struct pruss_private_data am437x_pruss1_data = {
.has_no_sharedram = false,
};
static const struct pruss_private_data am437x_pruss0_data = {
.has_no_sharedram = true,
};
static const struct of_device_id pruss_of_match[] = {
{ .compatible = "ti,am3356-pruss" },
{ .compatible = "ti,am4376-pruss0", .data = &am437x_pruss0_data, },
{ .compatible = "ti,am4376-pruss1", .data = &am437x_pruss1_data, },
{},
};
MODULE_DEVICE_TABLE(of, pruss_of_match);