feat(pcm): prove PCM/I2S clock enable

Sources/Application/Application.swift

@@ -1668,6 +1668,22 @@ struct Application {
     uartPutDec(UInt64(kernel_pwm4_restore()))
     uartPuts("\n")
 
+    // Runtime V142: PCM/I2S clock + CS enable. UART token only.
+    // Fail-closed CM_PCM + PCM_CS EN readback + leftover restore.
+    // No pin-mux. No FIFO. No output claim. No boot event emit.
+    // No EL0 enter after GENET.
+    uartPuts("runtime v142: PCM enable\n")
+    let pcm_ok_boot = kernel_pcm_selftest()
+    uartPuts("pcm ok=")
+    uartPutDec(UInt64(pcm_ok_boot))
+    uartPuts(" version=142 clk=")
+    uartPutDec(UInt64(kernel_pcm_clk()))
+    uartPuts(" en=")
+    uartPutDec(UInt64(kernel_pcm_en()))
+    uartPuts(" restore=")
+    uartPutDec(UInt64(kernel_pcm_restore()))
+    uartPuts("\n")
+
     kernel_event_emit(KERNEL_EVENT_KIND_SELFTEST, 22, UInt(kernel_pool_selftest()), UInt(kernel_pool_count()))
     kernel_event_emit(KERNEL_EVENT_KIND_SELFTEST, 23, UInt(heap_fragmentation_selftest()), UInt(kernel_pool_pressure_selftest()))
     kernel_event_emit(KERNEL_EVENT_KIND_SELFTEST, 24, UInt(kernel_driver_registry_selftest()), UInt(kernel_driver_count()))

Sources/Application/UARTShell.swift

@@ -100,7 +100,7 @@ func uartPutShellBufferSlice(_ start: UInt32, _ len: UInt32) {
 }
 
 let SHELL_COMMAND_LIST =
-  "commands=help,protocol,status,heap,queues,tasks,tasks2,kobjects,drivers,drivercheck,mailboxes,sendtest,supervisor,health,handlecheck,capcheck,events,runtime,agent,certificate,sched,sched2,sched3,sched4,sched5,sched6,sched7,sched8,sched9,sched10,sched11,sched12,cores,locks,runqueues,diag,irqs,timers,memcheck,faults,retained,retained-clear,memmap,mmu,pools,poolcheck,heapfrag,poolstats,frames,heapcheck,framecheck,stress,frameprobe,bootcert,canceltest,taskcheck,channeltest,bootcheck,soak,heap-invalid-free-test,heap-double-free-test,panic-test,fault-test,reboot,vmm,asplit,el0,syscall,uaccess,usermode,process,loader,multiprocess,sdhci,card,block,fat32,mailbox,framebuf,console,pcie,vl805,xhci,genet,genet2,genet3,genet4,gpio,genet5,genet6,genet7,genet8,genet9,genet10,genet11,genet12,i2c,pwm,i2c2,spi2,stimer,sdload,sdls,sdfile,sdovl,sdovf,sdiss,gpio2,stimer2,pwm2,gpio3,stimer3,mboxt,mboxc,wdog2,mboxv,rng,dma2,sdwr,sdmk,sdrd,sdst,sdscr,sdss,sdbus,sdmb,sdsw,sdmw,sdbc,sdfi,sdfb,sdfm,sdrm,genet13,genet14,genet15,genet16,genet17,genet18,genet19,genet20,genet21,genet22,genet23,genet24,genet25,genet26,genet27,genet28,genet29,genet30,genet31,genet32,genet33,genet34,pwm3,gpio4,pwm4"
+  "commands=help,protocol,status,heap,queues,tasks,tasks2,kobjects,drivers,drivercheck,mailboxes,sendtest,supervisor,health,handlecheck,capcheck,events,runtime,agent,certificate,sched,sched2,sched3,sched4,sched5,sched6,sched7,sched8,sched9,sched10,sched11,sched12,cores,locks,runqueues,diag,irqs,timers,memcheck,faults,retained,retained-clear,memmap,mmu,pools,poolcheck,heapfrag,poolstats,frames,heapcheck,framecheck,stress,frameprobe,bootcert,canceltest,taskcheck,channeltest,bootcheck,soak,heap-invalid-free-test,heap-double-free-test,panic-test,fault-test,reboot,vmm,asplit,el0,syscall,uaccess,usermode,process,loader,multiprocess,sdhci,card,block,fat32,mailbox,framebuf,console,pcie,vl805,xhci,genet,genet2,genet3,genet4,gpio,genet5,genet6,genet7,genet8,genet9,genet10,genet11,genet12,i2c,pwm,i2c2,spi2,stimer,sdload,sdls,sdfile,sdovl,sdovf,sdiss,gpio2,stimer2,pwm2,gpio3,stimer3,mboxt,mboxc,wdog2,mboxv,rng,dma2,sdwr,sdmk,sdrd,sdst,sdscr,sdss,sdbus,sdmb,sdsw,sdmw,sdbc,sdfi,sdfb,sdfm,sdrm,genet13,genet14,genet15,genet16,genet17,genet18,genet19,genet20,genet21,genet22,genet23,genet24,genet25,genet26,genet27,genet28,genet29,genet30,genet31,genet32,genet33,genet34,pwm3,gpio4,pwm4,pcm"
 
 func printShellReady() {
   uartPuts("shell ready \(SHELL_COMMAND_LIST)\n")
@@ -3114,6 +3114,19 @@ func printPwm4() {
   uartPuts("\n")
 }
 
+func printPcm() {
+  _ = kernel_pcm_selftest()
+  uartPuts("pcm ok=")
+  uartPutDec(UInt64(kernel_pcm_ok()))
+  uartPuts(" version=142 clk=")
+  uartPutDec(UInt64(kernel_pcm_clk()))
+  uartPuts(" en=")
+  uartPutDec(UInt64(kernel_pcm_en()))
+  uartPuts(" restore=")
+  uartPutDec(UInt64(kernel_pcm_restore()))
+  uartPuts("\n")
+}
+
 func printPoolName(_ pool: UInt32) {
   var i: UInt32 = 0
   let n = kernel_pool_name_len(pool)
@@ -4136,6 +4149,8 @@ func dispatchShellCommand(_ commandStart: UInt32, _ commandLen: UInt32, _ reques
     printGpio4()
   } else if shellBufferSliceEquals(commandStart, commandLen, "pwm4") {
     printPwm4()
+  } else if shellBufferSliceEquals(commandStart, commandLen, "pcm") {
+    printPcm()
   } else if shellBufferSliceEquals(commandStart, commandLen, "pools") {
     printPools()
   } else if shellBufferSliceEquals(commandStart, commandLen, "poolcheck") {

Sources/Support/include/Support.h

@@ -1640,6 +1640,13 @@ unsigned int  kernel_pwm4_pwm1(void);
 unsigned int  kernel_pwm4_en(void);
 unsigned int  kernel_pwm4_restore(void);
 
+// V142: PCM/I2S clock + CS enable after GENET. Fail-closed readback. No EL0.
+int           kernel_pcm_selftest(void);
+int           kernel_pcm_ok(void);
+unsigned int  kernel_pcm_clk(void);
+unsigned int  kernel_pcm_en(void);
+unsigned int  kernel_pcm_restore(void);
+
 // V84: system timer CLO/CHI + four compare slots. Read-only. No boot emit.
 int           kernel_stimer_selftest(void);
 int           kernel_stimer_ok(void);

Sources/Support/kernel_pcm.c

@@ -0,0 +1,114 @@
+// Runtime V142: BCM2711 PCM/I2S clock + CS enable after GENET.
+// New unused block (0xFE203000). Fail-closed CM_PCM OSC + PCM_CS EN
+// write+readback + leftover restore. TXON/RXON/DMAEN stay clear.
+// No pin-mux. No FIFO. No output/audio claim.
+// Does not write PWM or GPIO event-detect registers.
+// No EL0 enter (I-abort esr=0xbf000002 elr=0x100002000 after GENET DMA).
+// No boot event emit.
+
+#include "Support.h"
+#include <stdint.h>
+
+#define PCM_BASE  0xFE203000UL
+#define CM_PCMCTL 0xFE101098UL
+#define CM_PCMDIV 0xFE10109CUL
+
+#define G32(off) (*(volatile uint32_t *)(PCM_BASE + (unsigned long)(off)))
+#define CM32(addr) (*(volatile uint32_t *)(addr))
+
+#define PCM_CS 0x00U
+
+#define PCM_CS_EN    (1U << 0)
+#define PCM_CS_RXON  (1U << 1)
+#define PCM_CS_TXON  (1U << 2)
+#define PCM_CS_DMAEN (1U << 9)
+/* Programmable leftover: EN/RXON/TXON/DMAEN. RXD/TXW/SYNC status is live. */
+#define PCM_CS_PROG  (PCM_CS_EN | PCM_CS_RXON | PCM_CS_TXON | PCM_CS_DMAEN)
+
+#define CM_PASSWD  0x5A000000U
+#define CM_SRC_OSC 1U
+#define CM_ENAB    (1U << 4)
+#define CM_BUSY    (1U << 7)
+#define CM_SRC_MASK  0x0FU
+#define CM_PROG      (CM_ENAB | CM_SRC_MASK)
+
+#define PCM_DIVI       50U
+#define PCM_WAIT_TICKS 108000UL /* ~2ms @ 54MHz CNTPCT */
+
+static int pcm_probed;
+static int pcm_ok_val;
+static unsigned int pcm_clk_val;
+static unsigned int pcm_en_val;
+static unsigned int pcm_restore_val;
+
+static int pcm_wait_busy(unsigned int want) {
+    unsigned long start = read_cntpct();
+    while ((read_cntpct() - start) < PCM_WAIT_TICKS) {
+        unsigned int ctl = CM32(CM_PCMCTL);
+        if (ctl == 0xFFFFFFFFU) return 0;
+        if (want) {
+            if ((ctl & CM_BUSY) != 0U) return 1;
+        } else if ((ctl & CM_BUSY) == 0U) {
+            return 1;
+        }
+    }
+    return 0;
+}
+
+int kernel_pcm_selftest(void) {
+    if (pcm_probed) return pcm_ok_val;
+    pcm_probed = 1;
+    pcm_ok_val = 0;
+    pcm_clk_val = 0;
+    pcm_en_val = 0;
+    pcm_restore_val = 0;
+
+    unsigned int saved_cm_ctl = CM32(CM_PCMCTL);
+    unsigned int saved_cm_div = CM32(CM_PCMDIV);
+    unsigned int saved_cs = G32(PCM_CS);
+    if (saved_cm_ctl == 0xFFFFFFFFU || saved_cm_div == 0xFFFFFFFFU || saved_cs == 0xFFFFFFFFU) {
+        return 0;
+    }
+
+    CM32(CM_PCMCTL) = CM_PASSWD | (saved_cm_ctl & 0x0FU);
+    if (pcm_wait_busy(0) == 0) {
+        CM32(CM_PCMCTL) = CM_PASSWD | (saved_cm_ctl & 0xFFU);
+        return 0;
+    }
+
+    CM32(CM_PCMDIV) = CM_PASSWD | (PCM_DIVI << 12);
+    CM32(CM_PCMCTL) = CM_PASSWD | CM_ENAB | CM_SRC_OSC;
+    if (pcm_wait_busy(1) != 0) pcm_clk_val = 1;
+
+    if (pcm_clk_val == 1U) {
+        unsigned int want = (saved_cs | PCM_CS_EN) & ~(PCM_CS_RXON | PCM_CS_TXON | PCM_CS_DMAEN);
+        G32(PCM_CS) = want;
+        unsigned int cs = G32(PCM_CS);
+        if ((cs & PCM_CS_EN) != 0U && (cs & (PCM_CS_RXON | PCM_CS_TXON | PCM_CS_DMAEN)) == 0U) {
+            pcm_en_val = 1;
+        }
+    }
+
+    G32(PCM_CS) = saved_cs;
+    CM32(CM_PCMCTL) = CM_PASSWD | (saved_cm_ctl & 0x0FU);
+    (void)pcm_wait_busy(0);
+    CM32(CM_PCMDIV) = CM_PASSWD | (saved_cm_div & 0x00FFFFFFU);
+    CM32(CM_PCMCTL) = CM_PASSWD | (saved_cm_ctl & 0xFFU);
+
+    if ((G32(PCM_CS) & PCM_CS_PROG) == (saved_cs & PCM_CS_PROG) &&
+        (CM32(CM_PCMCTL) & CM_PROG) == (saved_cm_ctl & CM_PROG) &&
+        (CM32(CM_PCMDIV) & 0x00FFFFFFU) == (saved_cm_div & 0x00FFFFFFU)) {
+        pcm_restore_val = 1;
+    }
+
+    if (pcm_clk_val == 1U && pcm_en_val == 1U && pcm_restore_val == 1U) {
+        pcm_ok_val = 1;
+        return 1;
+    }
+    return 0;
+}
+
+int          kernel_pcm_ok(void)      { return pcm_ok_val; }
+unsigned int kernel_pcm_clk(void)     { return pcm_clk_val; }
+unsigned int kernel_pcm_en(void)      { return pcm_en_val; }
+unsigned int kernel_pcm_restore(void) { return pcm_restore_val; }

docs/ROADMAP.md

@@ -154,6 +154,7 @@ Turn the static identity-map MMU into a real virtual-memory system and run code
 - [x] V139 PWM GPIO12 ALT0 pin-mux after GENET (`pwm3 ok=1 version=139 pin=12 alt=1 restore=1`). Fail-closed `GPFSEL1` ALT0 readback + leftover restore; UART GPIO14/15 FSEL bits unchanged; no pull writes; no output claim; no EL0.
 - [x] V140 GPIO42 rising-edge detect after GENET (`gpio4 ok=1 version=140 pin=42 rise=1 restore=1`). Fail-closed `GPREN1`/`GPEDS1` after a SET edge; leftover restore; no UART; no ALT0; no EL0.
 - [x] V141 PWM1 channel-1 program after GENET (`pwm4 ok=1 version=141 pwm1=1 en=1 restore=1`). Fail-closed `PWM1` RNG1/DAT1/PWEN1 write+readback + leftover restore; no pin-mux; no output claim; no EL0.
+- [x] V142 PCM/I2S enable after GENET (`pcm ok=1 version=142 clk=1 en=1 restore=1`). Fail-closed `CM_PCM` OSC + `PCM_CS` EN write+readback + leftover restore; no pin-mux; no TX/RX/FIFO; no output/audio claim; no EL0.
 - [x] V94 GPIO26 PUP_PDN write+readback after GENET (`gpio3 ok=1 version=94 pin=26 up=1 dn=1`). REG1 only; restore; no UART; no EL0.
 - [x] V95 system timer C3 match after GENET (`stimer3 ok=1 version=95 chan=3 match=1`). ARM C3 only; no C0/C1/C2 writes; park after match; no EL0.
 - [x] V96 mailbox GET_TEMPERATURE after GENET (`mboxt ok=1 version=96 temp=`). Millidegrees; fail-closed range; no EL0.

scripts/netboot/net-iterate.sh

@@ -497,6 +497,8 @@ PY
       && printf '%s' "$serial_delta" | grep -qa "gpio4 ok=1 version=140 pin=42 rise=" \
       && printf '%s' "$serial_delta" | grep -qa "runtime v141: PWM1 program" \
       && printf '%s' "$serial_delta" | grep -qa "pwm4 ok=1 version=141 pwm1=1 en=" \
+      && printf '%s' "$serial_delta" | grep -qa "runtime v142: PCM enable" \
+      && printf '%s' "$serial_delta" | grep -qa "pcm ok=1 version=142 clk=1 en=" \
       && printf '%s' "$serial_delta" | grep -qa "vmmcheck ok=1" \
       && printf '%s' "$serial_delta" | grep -qa "asplit ok=1 version=46" \
       && printf '%s' "$serial_delta" | grep -qa "el0 ok=1 version=47" \
@@ -822,6 +824,8 @@ PY
         probe_shell "gpio4" "^gpio4 ok=1 version=140 pin=42 rise="
         # V141: PWM1 channel-1 program. Fail-closed readback. No EL0.
         probe_shell "pwm4" "^pwm4 ok=1 version=141 pwm1=1 en="
+        # V142: PCM/I2S clock + CS enable. Fail-closed readback. No EL0.
+        probe_shell "pcm" "^pcm ok=1 version=142 clk=1 en="
         # probe shell: req-status
         probe_shell "req id=25 cmd=status" "^resp id=25 ok=1 cmd=status end"
         # probe shell: canceltest

scripts/netboot/netboot-doctor.sh

@@ -357,6 +357,8 @@ while [ "$SECONDS" -lt "$deadline" ]; do
       && printf '%s' "$serial_delta" | grep -q "gpio4 ok=1 version=140 pin=42 rise=" \
       && printf '%s' "$serial_delta" | grep -q "runtime v141: PWM1 program" \
       && printf '%s' "$serial_delta" | grep -q "pwm4 ok=1 version=141 pwm1=1 en=" \
+      && printf '%s' "$serial_delta" | grep -q "runtime v142: PCM enable" \
+      && printf '%s' "$serial_delta" | grep -q "pcm ok=1 version=142 clk=1 en=" \
       && printf '%s' "$serial_delta" | grep -q "vmmcheck ok=1" \
       && printf '%s' "$serial_delta" | grep -q "asplit ok=1 version=46" \
       && printf '%s' "$serial_delta" | grep -q "el0 ok=1 version=47" \

tests/test_runtime_pcm_v142_contract.py

@@ -0,0 +1,81 @@
+"""EPIC G V142: PCM/I2S clock+enable after GENET. Fail-closed readback. No EL0."""
+
+import pathlib
+
+
+ROOT = pathlib.Path(__file__).resolve().parents[1]
+
+
+def read_repo(path: str) -> str:
+    return (ROOT / path).read_text()
+
+
+def test_pcm_enable_fail_closed_without_el0() -> None:
+    load = read_repo("Sources/Support/kernel_pcm.c")
+    pwm2 = read_repo("Sources/Support/kernel_pwm2.c")
+    pwm4 = read_repo("Sources/Support/kernel_pwm4.c")
+    support = read_repo("Sources/Support/include/Support.h")
+    app = read_repo("Sources/Application/Application.swift")
+    shell = read_repo("Sources/Application/UARTShell.swift")
+    iterate = read_repo("scripts/netboot/net-iterate.sh")
+    doctor = read_repo("scripts/netboot/netboot-doctor.sh")
+    scheduler = read_repo("Sources/Support/kernel_scheduler.c")
+    roadmap = read_repo("docs/ROADMAP.md")
+
+    assert "0xFE203000" in load
+    assert "0xFE101098" in load
+    assert "PCM_CS" in load
+    assert "PCM_CS_EN" in load
+    assert "CM_PCMCTL" in load
+    assert "int           kernel_pcm_selftest(void);" in support
+    assert "unsigned int  kernel_pcm_clk(void);" in support
+    assert "unsigned int  kernel_pcm_en(void);" in support
+    assert "unsigned int  kernel_pcm_restore(void);" in support
+    assert 'uartPuts("runtime v142: PCM enable\\n")' in app
+    assert 'uartPuts("pcm ok=")' in app
+    assert "kernel_event_emit(KERNEL_EVENT_KIND_SELFTEST, 142" not in app
+    assert "func printPcm()" in shell
+    assert 'shellBufferSliceEquals(commandStart, commandLen, "pcm")' in shell
+    assert ",pwm4,pcm" in shell
+    assert 'grep -qa "pcm ok=1 version=142 clk=1 en="' in iterate
+    assert 'probe_shell "pcm" "^pcm ok=1 version=142 clk=1 en="' in iterate
+    assert 'grep -q "pcm ok=1 version=142 clk=1 en="' in doctor
+    assert "V142 PCM/I2S enable" in roadmap
+    assert "kernel_pcm_selftest" not in scheduler
+    assert "alloc_dma" not in load
+    assert "kernel_event_emit" not in load
+    assert "kernel_enter_el0_and_wait" not in load
+    assert "0xbf000002" in load
+    assert "watchdog_reset_now" not in load
+    # New unused PCM block, not a PWM-DAT / edge / ALT0 / SPI0-TA clone.
+    assert "0xFE20C000" not in load
+    assert "0xFE20C800" not in load
+    assert "PWM_DAT1" not in load
+    assert "GPREN" not in load
+    assert "GPEDS" not in load
+    assert "GPFSEL" not in load
+    assert "ALT0" not in load
+    assert "SPI_CS_TA" not in load
+    assert "0xFE204000" not in load
+    assert "PUP_PDN" not in load
+    assert "RBUF_64B_EN" not in load
+    assert "DMA_TX_DO_CSUM" not in load
+    assert "CMD_LCL_LOOP_EN" not in load
+    assert "EXT_RGMII_OOB_CTRL" not in load
+    assert "PCM_CS_TXON" in load
+    assert "PCM_CS_RXON" in load
+    assert "0xFE203000" not in pwm2
+    assert "0xFE203000" not in pwm4
+    assert "ping -c 2" in iterate
+    assert "SOCK_STREAM" in iterate
+    assert "sched12" in iterate
+
+
+def test_no_boot_el0_enter_after_genet12() -> None:
+    """sys_socket after GENET DMA I-aborted; do not ship a second boot EL0 enter."""
+    app = read_repo("Sources/Application/Application.swift")
+    after = app.split("kernel_genet12_selftest", 1)[1]
+    assert "kernel_enter_el0_and_wait" not in after
+    assert "kernel_socket_selftest" not in after
+    assert "kernel_pcm_selftest" in after
+    assert "kernel_spi3_selftest" not in after