Merge #352

352: Add the Cortex-M7 TCM and cache access control registers. r=adamgreig a=rcls

Add the Cortex-M7 TCM and cache access control registers.

These are documented in the Cortex-M7 generic user guide (ARM DUI 0646C). 

I'm not sure what feature gate these should be on - should I add a new one for Cortex-M7? Currently I have them on `not(armv6m)` - they do not appear to be in the ARMv7M architecture documentation, so I presume they are M7 specific.

Co-authored-by: Ralph Loader <ralph1loader@gmail.com>

1 files changed, 93 insertions, 0 deletions

diff --git a/src/peripheral/ac.rs b/src/peripheral/ac.rs
new file mode 100644
index 0000000..1ac5be1
--- /dev/null
+++ b/src/peripheral/ac.rs
@@ -0,0 +1,93 @@
+//! Cortex-M7 TCM and Cache access control.
+
+use volatile_register::RW;
+
+/// Register block
+#[repr(C)]
+pub struct RegisterBlock {
+    /// Instruction Tightly-Coupled Memory Control Register
+    pub itcmcr: RW<u32>,
+    /// Data Tightly-Coupled Memory Control Register
+    pub dtcmcr: RW<u32>,
+    /// AHBP Control Register
+    pub ahbpcr: RW<u32>,
+    /// L1 Cache Control Register
+    pub cacr: RW<u32>,
+    /// AHB Slave Control Register
+    pub ahbscr: RW<u32>,
+    reserved0: u32,
+    /// Auxilary Bus Fault Status Register
+    pub abfsr: RW<u32>,
+}
+
+/// ITCMCR and DTCMCR TCM enable bit.
+pub const TCM_EN: u32 = 1;
+
+/// ITCMCR and DTCMCR TCM read-modify-write bit.
+pub const TCM_RMW: u32 = 2;
+
+/// ITCMCR and DTCMCR TCM rety phase enable bit.
+pub const TCM_RETEN: u32 = 4;
+
+/// ITCMCR and DTCMCR TCM size mask.
+pub const TCM_SZ_MASK: u32 = 0x78;
+
+/// ITCMCR and DTCMCR TCM shift.
+pub const TCM_SZ_SHIFT: usize = 3;
+
+/// AHBPCR AHBP enable bit.
+pub const AHBPCR_EN: u32 = 1;
+
+/// AHBPCR AHBP size mask.
+pub const AHBPCR_SZ_MASK: u32 = 0x0e;
+
+/// AHBPCR AHBP size shit.
+pub const AHBPCR_SZ_SHIFT: usize = 1;
+
+/// CACR Shared cachedable-is-WT for data cache.
+pub const CACR_SIWT: u32 = 1;
+
+/// CACR ECC in the instruction and data cache (disable).
+pub const CACR_ECCDIS: u32 = 2;
+
+/// CACR Force Write-Through in the data cache.
+pub const CACR_FORCEWT: u32 = 4;
+
+/// AHBSCR AHBS prioritization control mask.
+pub const AHBSCR_CTL_MASK: u32 = 0x03;
+
+/// AHBSCR AHBS prioritization control shift.
+pub const AHBSCR_CTL_SHIFT: usize = 0;
+
+/// AHBSCR Threshold execution prioity for AHBS traffic demotion, mask.
+pub const AHBSCR_TPRI_MASK: u32 = 0x7fc;
+
+/// AHBSCR Threshold execution prioity for AHBS traffic demotion, shift.
+pub const AHBSCR_TPRI_SHIFT: usize = 2;
+
+/// AHBSCR Failness counter initialization value, mask.
+pub const AHBSCR_INITCOUNT_MASK: u32 = 0xf800;
+
+/// AHBSCR Failness counter initialization value, shift.
+pub const AHBSCR_INITCOUNT_SHIFT: usize = 11;
+
+/// ABFSR Async fault on ITCM interface.
+pub const ABFSR_ITCM: u32 = 1;
+
+/// ABFSR Async fault on DTCM interface.
+pub const ABFSR_DTCM: u32 = 2;
+
+/// ABFSR Async fault on AHBP interface.
+pub const ABFSR_AHBP: u32 = 4;
+
+/// ABFSR Async fault on AXIM interface.
+pub const ABFSR_AXIM: u32 = 8;
+
+/// ABFSR Async fault on EPPB interface.
+pub const ABFSR_EPPB: u32 = 16;
+
+/// ABFSR Indicates the type of fault on the AXIM interface, mask.
+pub const ABFSR_AXIMTYPE_MASK: u32 = 0x300;
+
+/// ABFSR Indicates the type of fault on the AXIM interface, shift.
+pub const ABFSR_AXIMTYPE_SHIFT: usize = 8;