From 4be0856fa34ef3b0681aeec669e50c13e394f145 Mon Sep 17 00:00:00 2001 From: Robert Jarzmik Date: Sat, 14 Feb 2015 23:38:39 +0100 Subject: [PATCH] ARM: pxa: transition to dmaengine phase 1 In order to slowly transition pxa to dmaengine, the legacy code will now rely on dmaengine to request a channel. This implies that PXA architecture selects DMADEVICES and PXA_DMA, which is not pretty. Yet it enables PXA drivers to be ported one by one, with part of them using dmaengine, and the other part using the legacy code. Signed-off-by: Robert Jarzmik --- arch/arm/mach-pxa/devices.c | 37 ++++++++++++++++++++++++++++ arch/arm/mach-pxa/pxa25x.c | 1 + arch/arm/mach-pxa/pxa27x.c | 1 + arch/arm/mach-pxa/pxa3xx.c | 1 + arch/arm/plat-pxa/dma.c | 22 ++++++++--------- arch/arm/plat-pxa/include/plat/dma.h | 15 +++++++++++ 6 files changed, 66 insertions(+), 11 deletions(-) diff --git a/arch/arm/mach-pxa/devices.c b/arch/arm/mach-pxa/devices.c index 35434662dc7c..e6ce669b54af 100644 --- a/arch/arm/mach-pxa/devices.c +++ b/arch/arm/mach-pxa/devices.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include "devices.h" @@ -1193,3 +1194,39 @@ void __init pxa2xx_set_spi_info(unsigned id, struct pxa2xx_spi_master *info) pd->dev.platform_data = info; platform_device_add(pd); } + +static struct mmp_dma_platdata pxa_dma_pdata = { + .dma_channels = 0, +}; + +static struct resource pxa_dma_resource[] = { + [0] = { + .start = 0x40000000, + .end = 0x4000ffff, + .flags = IORESOURCE_MEM, + }, + [1] = { + .start = IRQ_DMA, + .end = IRQ_DMA, + .flags = IORESOURCE_IRQ, + }, +}; + +static u64 pxadma_dmamask = 0xffffffffUL; + +static struct platform_device pxa2xx_pxa_dma = { + .name = "pxa-dma", + .id = 0, + .dev = { + .dma_mask = &pxadma_dmamask, + .coherent_dma_mask = 0xffffffff, + }, + .num_resources = ARRAY_SIZE(pxa_dma_resource), + .resource = pxa_dma_resource, +}; + +void __init pxa2xx_set_dmac_info(int nb_channels) +{ + pxa_dma_pdata.dma_channels = nb_channels; + pxa_register_device(&pxa2xx_pxa_dma, &pxa_dma_pdata); +} diff --git a/arch/arm/mach-pxa/pxa25x.c b/arch/arm/mach-pxa/pxa25x.c index 23a90c62ec11..1dc85ffc3e20 100644 --- a/arch/arm/mach-pxa/pxa25x.c +++ b/arch/arm/mach-pxa/pxa25x.c @@ -206,6 +206,7 @@ static int __init pxa25x_init(void) register_syscore_ops(&pxa_irq_syscore_ops); register_syscore_ops(&pxa2xx_mfp_syscore_ops); + pxa2xx_set_dmac_info(16); pxa_register_device(&pxa25x_device_gpio, &pxa25x_gpio_info); ret = platform_add_devices(pxa25x_devices, ARRAY_SIZE(pxa25x_devices)); diff --git a/arch/arm/mach-pxa/pxa27x.c b/arch/arm/mach-pxa/pxa27x.c index b5abdeb5bb2d..e6aae9e8adfb 100644 --- a/arch/arm/mach-pxa/pxa27x.c +++ b/arch/arm/mach-pxa/pxa27x.c @@ -310,6 +310,7 @@ static int __init pxa27x_init(void) if (!of_have_populated_dt()) { pxa_register_device(&pxa27x_device_gpio, &pxa27x_gpio_info); + pxa2xx_set_dmac_info(32); ret = platform_add_devices(devices, ARRAY_SIZE(devices)); } diff --git a/arch/arm/mach-pxa/pxa3xx.c b/arch/arm/mach-pxa/pxa3xx.c index bd4cbef15ccf..aa85ec1a3065 100644 --- a/arch/arm/mach-pxa/pxa3xx.c +++ b/arch/arm/mach-pxa/pxa3xx.c @@ -431,6 +431,7 @@ static int __init pxa3xx_init(void) if (of_have_populated_dt()) return 0; + pxa2xx_set_dmac_info(32); ret = platform_add_devices(devices, ARRAY_SIZE(devices)); if (ret) return ret; diff --git a/arch/arm/plat-pxa/dma.c b/arch/arm/plat-pxa/dma.c index d92f07f6ecfb..de2b061889ec 100644 --- a/arch/arm/plat-pxa/dma.c +++ b/arch/arm/plat-pxa/dma.c @@ -289,7 +289,8 @@ int pxa_request_dma (char *name, pxa_dma_prio prio, /* try grabbing a DMA channel with the requested priority */ for (i = 0; i < num_dma_channels; i++) { if ((dma_channels[i].prio == prio) && - !dma_channels[i].name) { + !dma_channels[i].name && + !pxad_toggle_reserved_channel(i)) { found = 1; break; } @@ -326,13 +327,14 @@ void pxa_free_dma (int dma_ch) local_irq_save(flags); DCSR(dma_ch) = DCSR_STARTINTR|DCSR_ENDINTR|DCSR_BUSERR; dma_channels[dma_ch].name = NULL; + pxad_toggle_reserved_channel(dma_ch); local_irq_restore(flags); } EXPORT_SYMBOL(pxa_free_dma); static irqreturn_t dma_irq_handler(int irq, void *dev_id) { - int i, dint = DINT; + int i, dint = DINT, done = 0; struct dma_channel *channel; while (dint) { @@ -341,16 +343,13 @@ static irqreturn_t dma_irq_handler(int irq, void *dev_id) channel = &dma_channels[i]; if (channel->name && channel->irq_handler) { channel->irq_handler(i, channel->data); - } else { - /* - * IRQ for an unregistered DMA channel: - * let's clear the interrupts and disable it. - */ - printk (KERN_WARNING "spurious IRQ for DMA channel %d\n", i); - DCSR(i) = DCSR_STARTINTR|DCSR_ENDINTR|DCSR_BUSERR; + done++; } } - return IRQ_HANDLED; + if (done) + return IRQ_HANDLED; + else + return IRQ_NONE; } int __init pxa_init_dma(int irq, int num_ch) @@ -372,7 +371,8 @@ int __init pxa_init_dma(int irq, int num_ch) spin_lock_init(&dma_channels[i].lock); } - ret = request_irq(irq, dma_irq_handler, 0, "DMA", NULL); + ret = request_irq(irq, dma_irq_handler, IRQF_SHARED, "DMA", + dma_channels); if (ret) { printk (KERN_CRIT "Wow! Can't register IRQ for DMA\n"); kfree(dma_channels); diff --git a/arch/arm/plat-pxa/include/plat/dma.h b/arch/arm/plat-pxa/include/plat/dma.h index a7b91dc06852..28848b344e2d 100644 --- a/arch/arm/plat-pxa/include/plat/dma.h +++ b/arch/arm/plat-pxa/include/plat/dma.h @@ -82,4 +82,19 @@ int pxa_request_dma (char *name, void pxa_free_dma (int dma_ch); +/* + * Cooperation with pxa_dma + dmaengine while there remains at least one pxa + * driver not converted to dmaengine. + */ +#if defined(CONFIG_PXA_DMA) +extern int pxad_toggle_reserved_channel(int legacy_channel); +#else +static inline int pxad_toggle_reserved_channel(int legacy_channel) +{ + return 0; +} +#endif + +extern void __init pxa2xx_set_dmac_info(int nb_channels); + #endif /* __PLAT_DMA_H */