ARM: davinci: da8xx: add remoteproc support

Add remoteproc platform device for controlling the DSP
on da8xx. The patch uses CMA-based reservation of physical
memory block for DSP use. A new kernel command-line parameter
has been added to allow boot-time specification of the physical
memory block.

Signed-off-by: Robert Tivy <rtivy@ti.com>
[nsekhar@ti.com: edit commit message for readability and
style improvements]
Signed-off-by: Sekhar Nori <nsekhar@ti.com>

1 files changed, 87 insertions, 1 deletions

diff --git a/arch/arm/mach-davinci/devices-da8xx.c b/arch/arm/mach-davinci/devices-da8xx.c
index cb97e07db284..bf572525175d 100644
--- a/arch/arm/mach-davinci/devices-da8xx.c
+++ b/arch/arm/mach-davinci/devices-da8xx.c
@@ -12,7 +12,7 @@
  */
 #include <linux/init.h>
 #include <linux/platform_device.h>
-#include <linux/dma-mapping.h>
+#include <linux/dma-contiguous.h>
 #include <linux/serial_8250.h>
 #include <linux/ahci_platform.h>
 #include <linux/clk.h>
@@ -714,6 +714,92 @@ int __init da850_register_mmcsd1(struct davinci_mmc_config *config)
 }
 #endif
 
+static struct resource da8xx_rproc_resources[] = {
+	{ /* DSP boot address */
+		.start		= DA8XX_SYSCFG0_BASE + DA8XX_HOST1CFG_REG,
+		.end		= DA8XX_SYSCFG0_BASE + DA8XX_HOST1CFG_REG + 3,
+		.flags		= IORESOURCE_MEM,
+	},
+	{ /* DSP interrupt registers */
+		.start		= DA8XX_SYSCFG0_BASE + DA8XX_CHIPSIG_REG,
+		.end		= DA8XX_SYSCFG0_BASE + DA8XX_CHIPSIG_REG + 7,
+		.flags		= IORESOURCE_MEM,
+	},
+	{ /* dsp irq */
+		.start		= IRQ_DA8XX_CHIPINT0,
+		.end		= IRQ_DA8XX_CHIPINT0,
+		.flags		= IORESOURCE_IRQ,
+	},
+};
+
+static struct platform_device da8xx_dsp = {
+	.name	= "davinci-rproc",
+	.dev	= {
+		.coherent_dma_mask	= DMA_BIT_MASK(32),
+	},
+	.num_resources	= ARRAY_SIZE(da8xx_rproc_resources),
+	.resource	= da8xx_rproc_resources,
+};
+
+#if IS_ENABLED(CONFIG_DA8XX_REMOTEPROC)
+
+static phys_addr_t rproc_base __initdata;
+static unsigned long rproc_size __initdata;
+
+static int __init early_rproc_mem(char *p)
+{
+	char *endp;
+
+	if (p == NULL)
+		return 0;
+
+	rproc_size = memparse(p, &endp);
+	if (*endp == '@')
+		rproc_base = memparse(endp + 1, NULL);
+
+	return 0;
+}
+early_param("rproc_mem", early_rproc_mem);
+
+void __init da8xx_rproc_reserve_cma(void)
+{
+	int ret;
+
+	if (!rproc_base || !rproc_size) {
+		pr_err("%s: 'rproc_mem=nn@address' badly specified\n"
+		       "    'nn' and 'address' must both be non-zero\n",
+		       __func__);
+
+		return;
+	}
+
+	pr_info("%s: reserving 0x%lx @ 0x%lx...\n",
+		__func__, rproc_size, (unsigned long)rproc_base);
+
+	ret = dma_declare_contiguous(&da8xx_dsp.dev, rproc_size, rproc_base, 0);
+	if (ret)
+		pr_err("%s: dma_declare_contiguous failed %d\n", __func__, ret);
+}
+
+#else
+
+void __init da8xx_rproc_reserve_cma(void)
+{
+}
+
+#endif
+
+int __init da8xx_register_rproc(void)
+{
+	int ret;
+
+	ret = platform_device_register(&da8xx_dsp);
+	if (ret)
+		pr_err("%s: can't register DSP device: %d\n", __func__, ret);
+
+	return ret;
+};
+
 static struct resource da8xx_rtc_resources[] = {
 	{
 		.start		= DA8XX_RTC_BASE,