From fed8b7e366e7c8f81e957ef91aa8f0a38e038c66 Mon Sep 17 00:00:00 2001 From: Mikko Perttunen Date: Wed, 28 Nov 2018 10:54:12 +0100 Subject: dt-bindings: tegra186-hsp: Add shared mailboxes Shared mailboxes are a mechanism to transport data from one processor in the system to another. They are bidirectional links with both a producer and a consumer. Interrupts are used to let the consumer know when data was written to the mailbox by the producer, and to let the producer know when the consumer has read the data from the mailbox. These interrupts are mapped to one or more "shared interrupts". Typically each processor in the system owns one of these shared interrupts. Add documentation to the device tree bindings about how clients can use mailbox specifiers to request a specific shared mailbox and select which direction they drive. Also document how to specify the shared interrupts in addition to the existing doorbell interrupt. Signed-off-by: Mikko Perttunen Acked-by: Jon Hunter Reviewed-by: Rob Herring Acked-by: Thierry Reding Signed-off-by: Thierry Reding Signed-off-by: Jassi Brar --- include/dt-bindings/mailbox/tegra186-hsp.h | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'include') diff --git a/include/dt-bindings/mailbox/tegra186-hsp.h b/include/dt-bindings/mailbox/tegra186-hsp.h index bcab5b7ca785..3bdec7a84d35 100644 --- a/include/dt-bindings/mailbox/tegra186-hsp.h +++ b/include/dt-bindings/mailbox/tegra186-hsp.h @@ -22,4 +22,15 @@ #define TEGRA_HSP_DB_MASTER_CCPLEX 17 #define TEGRA_HSP_DB_MASTER_BPMP 19 +/* + * Shared mailboxes are unidirectional, so the direction needs to be specified + * in the device tree. + */ +#define TEGRA_HSP_SM_MASK 0x00ffffff +#define TEGRA_HSP_SM_FLAG_RX (0 << 31) +#define TEGRA_HSP_SM_FLAG_TX (1 << 31) + +#define TEGRA_HSP_SM_RX(x) (TEGRA_HSP_SM_FLAG_RX | ((x) & TEGRA_HSP_SM_MASK)) +#define TEGRA_HSP_SM_TX(x) (TEGRA_HSP_SM_FLAG_TX | ((x) & TEGRA_HSP_SM_MASK)) + #endif -- cgit v1.2.3